Got 3 of the challenges beaten on Insane (though granted I did nothing on Assault), and beat Ramparts on Insane.
The monk is way overpowered for the higher difficulty due to Ensnare Aura. Really anything moving at 20% (or less speed) might as well be taking 5X the damage and move at full speed, and it'd actually be better because at least you can't hit 50 mobs with one piercing shot that way. It's not that monk by itself is powerful. You'll pretty much never be able to kill Ogres or even lightning immunes with just a monk, but Ensnare Aura pretty much removes anything besides Wyverns, Ogres, and lightning immunes. An Insane level with or without Ensnare Aura isn't even the same kind of game. It's not clear to me if the Insane levels are even doable without Ensnare Aura.
The easiest fix should be to make everything on Insane immune to Ensnare Aura since messing with the % is dangerous (it might be too weak at lower levels then). Strength drain aura at least uses 6 DUs and it's still pretty much impossible to deal with Ogres with only towers even with the aura (though it gives you time to get there to deal with the Ogre). Lightning Aura appears to be overpowered simply because everything inside the lightning aura is moving at 20% speed so it might as well be doing 5 times the damage. Alternatively they could give everything snare resistance kind of like Diablo 2 stuff resists lifetap effects on Hell, or EQ stuff resist slow. But I never really liked the fact that because you'll never die in Diablo 2 with full drain or that a mob slowed 75% in EQ basically is incapable of killing anybody, so you put in some secret modifier that makes life drain work about 1/6th as much as it claims, and slow only slows the mob 5%, because that means anyone new to the game is going to be wondering why nothing seems to be working as advertised. You could make some of the units immune (Ogres are already immune) but again that's just confusing if the rule suddenly changes. You can simply make it so that you can't use Ensnare Aura at all if the game is on insane. It'd be no different than how cores do not heal on Insane but heal on any other mode and there won't be any confusion as long as you pop up a message like 'cannot summon this on this mode'.
Dark Elf Warriors are really hard to deal with since they randomly run past all your defenses without taking damage. I think they're probably at least somewhat bugged. Overall, I don't like to solo on insane because it basically goes like this:
Wave 1: monk frantically put down auras and switch back to DPS character before time runs out.
Wave 2 + 3: Tower character build defense through the entire wave(s). Hope you memorized the exact layout of the map because getting an extra Tower up at the right place can be the difference between winning or not.
Wave 4+: DPS character is mandatory because you can't possibly deal with Ogres otherwise. If Ogres show up when you're on your Tower character, it's pretty much game over, but they usually don't show up until wave 4 or so.
Since auras basically last forever, there's really no point for a Tower monk to appear at any time other than the build phase of Wave 1. Auras aren't like Towers as there is no remote possibility you'll lose them unless you're in a map like Glitterhelm and fell asleep for 2 waves and forgot where your weakest aura was. Of course most of the time there is no reason to have any Tower-based character to stay in combat phase either. The real problem is that since Tower stats do not give hero speed or hero casting time (obviously), that means a character specialized for Tower isn't even very good at repairing/building Towers in mid combat compared to one specialized for DPS (who will at least have speed maxed, and usually a decent amount of casting since HP isn't too useful). I suppose it'd not make sense to gain hero speed from Tower stats, but the other Tower stats should at least let you repair/build Towers way faster than someone who only has points in hero stats.
