Doing 7 towers is going to be rough, man, plus four subs!!! That's a lot of real estate.
To be honest... I like the sliding door covering the bar idea. I think you should consider a retractable transparent screen: no need to f with building a false wall. Great idea creating an equipment room in a closet: just be certain to ventilate, and make certain you can access it all.
Keeping the fan? or losing it for the projector??? Getting the projector off the floor would be smart I think... again space issues.
Thinking about Surrounds... have you thought about going 5.x.4... or are you going to keep with 7 on the bed layer? Admittedly, I've entertained going with a Rear Center instead of stereo Rears: Small room, add in Atmos, I suspect that change is workable with the right gear.