Whenever minecraft gets boring I usually just make a new world and start over again, theres not enough to do. Perhaps if you expand on the tactics of skeletons, creepers, and such... and also add more enemies, you could put in abilities, which can be pretty much anything that grant special combos, to raining fire.... It's not very realistic if thats what you are going for but it seems like it would just add fun, cause games aren't supposed to be entirely realistic, I mean minecraft is made out of blocks.... Leveling up would just be a goal in the game to get from one level to the next and unlock perhaps more abilities, and also what i was thinking was to have level requirements for weapons, diamond would of course be the highest level working down to poor wooden,Also for armor. Experience would go nicely with leveling up, you kill a creeper you get 20 Exp. A spider, 15, etc... This is only a suggestion and I understand if you don't want to add it please don't treat it as if I somehow broke into your house and forced you to upload this to minecraft. Thanks, Bye bye
minecraft is a sandbox game were you can do what you want if you add levels and classes ect you restrict things which is not what minecraft is and should never be
Minecraft is not, and never will be, an RPG.
no classes none of that =)