I've been working on a fairly low-res pixel-art style game and have been putting effort into allowing the player access to the sprite sheets. There are a lot of hard-coded graphics, but certain files are external. Most importantly: character weapons and gear.

I've got a system to allow the player to edit the weapon stats and an algorithm that determines the item cost based on the input stats. So in theory player's can make a 9999 damage super-high ROF weapon, but they'd spend a stupid amount of time gathering the resources needed to build it.

I should also note - this isn't the "main theme" of the game. It's just something of an aside. Something i thought would be neat, but not vital. I've got a collection of pre-made weapons/gear/etc for the player to use should they decide not to make custom stuff.

So far, I haven't had any technical issues with it yet, but actual gameplay isn't to a "functional" level yet, so 0 balancing has been done.

I rarely see much customization of this type and I'm kind of expecting to find out why later down the road. If anyone has any insight as to why this is a bad idea, I'd be happy to hear it, since it would at least let me consider fixes, or nix it completely. I've often gone down the "neat idea" path just to find at the end is a disaster or technical nightmare.

There is no multiplayer, so balancing PVP isn't going to be an issue.

If there's no multiplayer, it doesn't seem like there would be a problem. The reason for rarely seeing it is probably that most players won't put the effort into modding the game. But the ones that do will probably upload their content to the internet somewhere for others to download and play with. Some of that custom content will be copyright-violating or obscene, but again this isn't really a problem in a single-player game. Even if someone uploads a Let's Play of your game to youtube and his character has a custom penis sword, that's not actually bad publicity. It does seem likely that players will go around your cost algorithm if they can, though. If that kind of thing can be hex-edited without too much difficulty, it will be.

I would make it easier by including a set of example mods and packs to encourage modding by showing how easy it is. You'll get more modders then.

You could also provide a hosting platform for people to upload their mods, but you'd have to have a terms of use and be prepared to take down violating content against those terms.

Even if someone uploads a Let's Play of your game to youtube and his character has a custom penis sword, that's not actually bad publicity. It does seem likely that players will go around your cost algorithm if they can, though. If that kind of thing can be hex-edited without too much difficulty, it will be.

I'm not too concerned about obscenity or cheating. Cheating probably matters more for multiplayer, but if someone wants to cheat in single player, that's their business. Besides, the item cost isn't contained within the external file, but is calculated internally during asset-loading.

I don't plan on hosting any copyright violations or obscene items, but any attention they bring will be welcome.

Even if someone uploads a Let's Play of your game to youtube and his character has a custom penis sword, that's not actually bad publicity. It does seem likely that players will go around your cost algorithm if they can, though. If that kind of thing can be hex-edited without too much difficulty, it will be.

I'm not too concerned about obscenity or cheating. Cheating probably matters more for multiplayer, but if someone wants to cheat in single player, that's their business. Besides, the item cost isn't contained within the external file, but is calculated internally during asset-loading.

I don't plan on hosting any copyright violations or obscene items, but any attention they bring will be welcome.

They would do something like stick the already-made item into their inventory or a chest in the game, rather than try to alter the cost. But yeah, basically in a single player game who cares if the player cheats.

I like the idea. Most games don't allow customization of items, both in looks or stats. If you're going to allow stat modifications, why not add in color customizations as well?

The only issue I see is that the game will need a lot of extra content to keep the player around long enough to mod their weapons and armor (like in late game). Often in early and mid game, I find a better weapon while I'm exploring a dungeon or doing a quest, and quickly ditch my previous item. I'll only hang onto something if it looks really awesome or has a stat I really want to keep.

The player will alter the game based on how much fun they want.

I wouldn't worry much about balance.