I was only able to get to the end of part 1 of ToEE because lammania just came down. We ran it on EE with 3 people and from what I can tell it isn't that hard, but there is a **** ton of mobs. We killed 1000 mobs before the end fight in part one. We skipped a few mobs but really why is there 1000+ mobs just in part one?
I was playing with a melee and haven't had a chance to bring other characters in there so this is coming from a melee monk perspective. Mobs aren't that bad, some hit fairly hard but they should be a bit tough. The fort saves on gargoyles and harpies seem to be low 90's, which is insane. Some of the saves they have are too high. 1000 + mobs and some mobs with unreal saves are really my only two complains. I have been able to run part one on EE, but those are my only two complaints.
Edit: Also the map resets when you leave an area. If you try and go back the map will be black. Very annoying.