My opinion:Set up like you would gig, if you have the room.
If you have the space, choose one wall of the room and say "that's the audience", arrange yourselves accordingly. Typically this means drummer in the back and everyone else in front. I set up on the snare/hi-hat side of the drummer. This way , when you get onstage at gig, presto! it's what you're used to.
PA would be used to monitor so speakers against the "audience" wall, facing the band. Mics pointed away form the speakers, towards the vocalist. If you are using a PA for anything besides vocals, you are probably turning up/drumming too loud.