A304: Gestalt is meant to be used for campaigns with small groups, not just in general. If the recommended party size for the module is 6ish, then you should probably use Gestalt if you have 4ish or fewer players. If the recommended party size is more like 4ish, then you should probably use Gestalt if you have 3ish or fewer players.
A305: No, Drink Like a Demon isn't ability damage, it's an untyped penalty.
A306: I don't know of any methods for removing curses from items without actually breaking the item. There's probably some application of the feat Craft Magic Arms and Armor that you can use.