One idea is to have only skills, but have only a certain number of skill slots, so that a charactor cant becomne omnipotent, and it would be a waste of time to have half stealth skills and half heavy armor because then you would get yorself nowere, accept a wek charactor, but it would allow you some variation to choose what kind of warrior you want to play weather you would like to be able to backstab go ambo or berserk, be able to survive on any planet you wanted with scout skills or if you want to be able to heal people up, it alows for a more individualistic characor instead of jusr another warror, or paladin or whatever else.

Another idea that I think would work is to make skill levels and only allow for a certain number of skills, so lets say novice backstab costs 1k exp, and then intermediate would be 10k up to lv 4 that would be like 100k, so it would take a crapload of time but it would also be well worth it, however it would be plain stupidity to after that take novice berserk up because then your backstab isnt worth much, but instead you ovice move silently and dvance that up to make you a more effective rouge, and if the person DID want to spend all that time playing a charactor than it only is right that he would be allitle omnipotent, because thats how much he put into the game, so you really invent your own class by maybe taking stealth/backstabbing skills or as a warrior you would want combat/defense skills, the key is to make it stupid to branch of into a dozen differnt classes, unless you live on your toilet with a refrigorator next to you and have the time in the world to advance your charactor, but you allow leeway, and at least the freedom to do whatever you want and specialize your charactor to his own unique touch.