Zombie's IS back, I was lucky enough to speak with who I believe was the head of ents last year about it, either way he was very high up taking down guest opinions and talking with staff, he also mentioned they was planning on adding a few more.
Personally I could see Haunted Hollow coming back IF security is stronger and dotted along the path in a way that's easy to monitor. I never got to do the original so this would be fantastic too.
2 mazes in The Towers sounds strange, I personally can't see the upstairs being used unless guests have to go up there first due to H&S, Imagine all the people falling on the steps e.t.c, which walk way would they use to go up to start? I personally hope they don't use it on a 2nd floor, I get major vertigo going up and would probably cause major issues although I'd push forward.
Hotels I can see mazes returning too, although I'm not sure exactly what, most likely carnival and something new.