I have started modding Dungeon Keeper I. The project is called "Afterlife". It will introduce a difficulty that would probably start from level 21 (after Skybird Trill).
Within a few days I'll upload the mod someplace here. It will only have modded first level (Red Carpet), but it will be fun, I believe.
I kinda have a feeling it will require tutorials. Because the strategy is slightly difficult. Well, you know my modding habbits
upd: in case you're unfamiliar with this game, it's a Diablo reversed (so to speak): you build dungeons, set traps, train your ugly & vicious monsters, use gold and magic to cut and slice silly heroes that would dare to enter your dark domain. "Evil is good" ©