Looks like you're off to a great start!
Speakers: If you can squeeze it, I'd still get the towers and a pair of subs. You just won't need quite so powerful of subs. But I'd rather spend the extra grand to get the towers, and just spend $500 less on each subwoofer. Which SVS can definitely accommodate (and they do multi sub discounts!)
Projector: Yes!
Screen: For fixed frame, I'd check out Elite Screens which are sold through Amazon. Your ambient lighting (and some personal preference) determine screen gain.
Receiver: Just personal preference but Denon, Marantz and Yamaha would always be my top picks. Again, on Amazon, if you're not interested in Atmos, you can find discontinued products at steep discount!
Speaker cables: buy a spool of 12 or 14 gauge, CL2/3 rated for in-wall. Period! This is a big argument amongst audiophiles, but the general consensus here is that there is no audible benefit to be attained from fancy cables. Stay FAR away from anyone selling cables that makes mention of 'better' dielectrics or involves using a 9v battery to 'power' the cable.