As far as balance goes. The original game was kinda tipped towards the players. Especially with 4 players. But the expansions help introduce some more Overload tricks that really balance the game out more and in some cases tip it towards the Overlord.
My groups main complaints with the game are
1) Once you play and adventure you lose everything. We understand from a design perspective that keeping equipment between adventures would just make the game to easy, but my players always get sad when they get a great mix of skills and equipment one game and lose it alll after they win. I guess the next expansion is gonna introduce campaign play rules to allow some carry over
2) The person who owns the game(ie me) is always stuck being the Overlord
