While designing an RPG, I was thinking about experience, level-ups and the experience requirement to achieve a level-up.
During that time, I thought of a way to implement exp requirement and exp gain. Here's how it'd work:

You have a static exp requirement - it stays the same regardless of your level. Let's say the requirement is 100.
You gain around 1 exp from each enemy you kill, though some smaller enemies with less health can give .5 or .25.

The amount of experience you gain is altered based on the level difference between you and the foe you kill. For each level under you the foe is, you gain 25% less experience. For each level above you the foe is, you gain 25% more experience with a maximum of 100% more experience. Using this system, foes 4 levels under you would provide 0 experience and foes 4 levels above you would provide double experience. The cap for bonus experience is 4 levels, so a foe 6 levels above you would still only give double experience.

This way, designing enemies' exp rewards can be made simpler. You can make a ground rule: those ordinary goblins with average health will give 1 experience per kill. The bigger ogres will give 1.5 experience since they're tougher. The sludge snakes with small health will give .25 experience. The bats with tiny health that are there to explode into guts for visual appeal will give .1 experience. I think you get the point now...

Another thing I didn't understand about systems that make it become harder and harder to level up as you gain more levels (such as MapleStory): if I'm gaining the same thing per level up (5 stat points, some health, whatever), why does it go from taking 2 minutes to level to 5 hours? Maybe it's just me, but I'd prefer playing a game where gaining levels stays as hard/easy as always so long as I fight enemies in my level range.

The way I see it, bonuses to this system over a typical MMORPG/RPG system would be:

• It saves you the trouble of designing a more complex system that ultimately does something very similar (makes players fight enemies their level in order to gain experience)
  
• Players may see this as a much simpler method
  
• It would be easier to design how much experience each creature gives
  
• It would be easier to design how much experience quests should give
  
  I was also thinking a level scaling feature for enemies could be included, which would make enemies gain levels (therefore, gain higher stats and such) if they're under the player's level and would make the player gain experience from them.
  
  So, that's about all...thanks for reading! What do you think?

The experience system you describe is one that I enjoy alot.
You can find it implemented in certain games like the Paper Mario series.

This way, designing enemies' exp rewards can be made simpler. You can make a ground rule: those ordinary goblins with average health will give 1 experience per kill. The bigger ogres will give 1.5 experience since they're tougher. The sludge snakes with small health will give .25 experience. The bats with tiny health that are there to explode into guts for visual appeal will give .1 experience. I think you get the point now...

Yea, this is how it's handled. Weak enemies (a level beneath you) give 1 exp. Medium enemies (your level) give 2 exp, stronger enemies (a level ahead of you) give 3 exp. If you happen to take out a powerful enemy ahead of time, while it's still many levels ahead of you, you can net 5 or 6 points. Bosses give like 50-75, depending on the boss and your level relative to the boss. Mini-bosses give maybe 15-25.

Another thing I didn't understand about systems that make it become harder and harder to level up as you gain more levels (such as MapleStory): if I'm gaining the same thing per level up (5 stat points, some health, whatever), why does it go from taking 2 minutes to level to 5 hours? Maybe it's just me, but I'd prefer playing a game where gaining levels stays as hard/easy as always so long as I fight enemies in my level range.[/quote]

You don't understand why it becomes harder and harder? It's because it makes you invest more time. More time you have to invest, the longer you'll stay with the game. The longer you stay with the game, the more monthly fees you have to pay them before you 'complete' the game.
It's an artificial and cheap way to drag out the enjoyment and content of the game to eek more money out of your players. The reason why it's easier when you start, is to get you addicted to leveling up through artificial rewards being handed out every so often... with the rewards then coming farther and farther apart, after you are already addicted.

The way I see it, bonuses to this system over a typical MMORPG/RPG system would be:

• It saves you the trouble of designing a more complex system that ultimately does something very similar (makes players fight enemies their level in order to gain experience)
  
• It would be easier to design how much experience each creature gives
  
• It would be easier to design how much experience quests should give
  
  [/quote]
  It's not more complex. It's the exact same formulas, just using exponential math to multiply everything. The extra same numbers you'd use for one, you could use for the other, and just apply a simple formula to convert it to the one used ingame.
  
  Some games (again, Paper Mario is a great example) also simplify the numbering of other game elements as well.
  Most games do something like take every price of every object, and multiply it by 100 to make it look more impressive. A potion doesn't cost 1 gold... it costs 100 gold! But you get 100 gold from every kill, so it doesn't actually change anything...
  
  When you punch someone, it does 200 damage instead of 2 damage! But, the enemy has 2000 health instead of 20 health, so it doesn't actually change anything...
  
  Paper Mario is one of those great games where you actually do 1 or 2 damage, and things actually do cost 3 or 4 coins. If you haven't played any of the Paper Mario games, I'd strongly strongly encourage it, as an example of game design that appeals to me personally. The first one (Paper Mario for the N64), or the second one (Paper Mario: The Thousand Year Door for the Gamecube (and backwards compatible on the Wii)). The third one (Super Paper Mario for the Wii) is different from the first two, and I can't vouch for it. But the first two are definitely examples of what you are talking about, so you should totally "research" them in your spare time.
  
  

  I was also thinking a level scaling feature for enemies could be included, which would make enemies gain levels (therefore, gain higher stats and such) if they're under the player's level and would make the player gain experience from them.[/quote]
  
  Now that idea is very hard to balance properly. But it's been done also, though infrequently. However, it's a separate idea entirely, (which I have no real opinions about).

Well i some cases the gap between levels is getting really big. But it should not be too easy either, completing a challenge is what games are about imo but everything in between levels should be as much fun as possible. Not like regular MMORPG's, kill 20 boars, collect 10 magic dust, trigger 15 traps, etc. Make the quests fun and the experience gap a bit shorter then usual and you end up with a very enjoyable rpg imo.

Another thing I didn't understand about systems that make it become harder and harder to level up as you gain more levels (such as MapleStory): if I'm gaining the same thing per level up (5 stat points, some health, whatever), why does it go from taking 2 minutes to level to 5 hours? Maybe it's just me, but I'd prefer playing a game where gaining levels stays as hard/easy as always so long as I fight enemies in my level range.

You don't understand why it becomes harder and harder? It's because it makes you invest more time. More time you have to invest, the longer you'll stay with the game. The longer you stay with the game, the more monthly fees you have to pay them before you 'complete' the game.
It's an artificial and cheap way to drag out the enjoyment and content of the game to eek more money out of your players. The reason why it's easier when you start, is to get you addicted to leveling up through artificial rewards being handed out every so often... with the rewards then coming farther and farther apart, after you are already addicted.

[/quote]
I figured that was why. It's a shame greed always penetrates into games and ruins the actual gameplay.

The way I see it, bonuses to this system over a typical MMORPG/RPG system would be:

• It saves you the trouble of designing a more complex system that ultimately does something very similar (makes players fight enemies their level in order to gain experience)
  
• It would be easier to design how much experience each creature gives
  
• It would be easier to design how much experience quests should give
  
  

It's not more complex. It's the exact same formulas, just using exponential math to multiply everything. The extra same numbers you'd use for one, you could use for the other, and just apply a simple formula to convert it to the one used ingame.

Some games (again, Paper Mario is a great example) also simplify the numbering of other game elements as well.
Most games do something like take every price of every object, and multiply it by 100 to make it look more impressive. A potion doesn't cost 1 gold... it costs 100 gold! But you get 100 gold from every kill, so it doesn't actually change anything...

When you punch someone, it does 200 damage instead of 2 damage! But, the enemy has 2000 health instead of 20 health, so it doesn't actually change anything...

Paper Mario is one of those great games where you actually do 1 or 2 damage, and things actually do cost 3 or 4 coins.
[/quote]

What I meant by less complex is that you don't have to use an experience requirement formula. It just stays at 100 instead of raising by (((X * Z) / (C * V)) + B), or whatever system you're using...it all seems so pointless if the end effect is the same, and it usually is. It also means you can simply give every enemy an exp reward of around .1-2, depending on how hard they are to kill and such.

EDIT: Another thing I forgot to say is that I think 'bloating' values like you mentioned can be helpful as long as it isn't excessively used. For example, 242 just looks better than 24.2 in my opinion, and if you're planning on making automated systems with formulas determining certain values, you may end up with decimal values like 24.2 frequently. Of course, you can round these values to the nearest integer, such as turning 24.2 into 24, but I think it's more appropriate in some situations to simply use larger numbers. It means certain things don't unfairly lose out on or gain extra damage/health/whatever you're calculating because you rounded the value up/down. However, I have seen RPGs that use 20,000 health straight off the bat from level 1, which I must say sounds like a bit of excessive bloating.

Well i some cases the gap between levels is getting really big. But it should not be too easy either, completing a challenge is what games are about imo but everything in between levels should be as much fun as possible. Not like regular MMORPG's, kill 20 boars, collect 10 magic dust, trigger 15 traps, etc. Make the quests fun and the experience gap a bit shorter then usual and you end up with a very enjoyable rpg imo.

I totally agree. Quests are always simple and completely dull in the latest F2P MMORPGs.