All I know is the location is an asylum - out east? I forget. And Jessica Lange and the person who played Tate will be back. They were my favorites (and Kate Mara but I haven't heard about her returning). Not sure when the new season starts.
i think the different parts will be ok. For the new folks, i'm excited about James Cromwell. I hope Adam Levine will be mostly naked. and chloe sevigny is pretty much usually awesome.
I think the change of venue and character can work if you connect the events. Maybe through a family (eg, Lange or Quinto plays one of their own relatives).