1. I really liked the festivities. Not sure what Kov is planning with that xD Oh and the dance parties were just players that randomly started dancing in a group and gradually more people joined. It happens in FH sometimes too.
2. There's currently Buttswing and Headswing as dance moves right? IT had those two, and also Thriller and Moonwalk. I'd like to see those again as well as new ones.
3. Those dance towers you mentioned weren't actual features in the game. People went into their map files and added a code which put in an invisible box called a 'collbox' which allows your character to stand in it. In IT, this collbox code was mostly used to be able to stand on objects such as rocks, because there was no mesh collision in IT. Collbox is available in FH too but you can't add it to default maps, and most people use mesh collision rather than collbox anyway.
4. You could only pick up items (accessories) in IT, since there is no items in FH, there's nothing to interact with xD I WOULD like the water splash back though, but a better one.