5.1.2 Atmos

I just read the article on Auto-3D. Sounds interesting. If I have two speakers for Atmos installed I will have 3 unused front ceiling speakers, so I think it will be possible.
I have a fan in the closet that vents to the attic. I will ask if that is enough.
No plans to ever sell but eventually our children might sell

i decided to with 5.1.4. It will be expensive, but I know it will be worth it

Just get 2 that sit near your ground speakers and bounce them off the ceiling.  They make speakers specifically for this 

The problem is in the installation. If I kept a 5.1 system I would be buy 2 Paradigm  floor speakers and center speaker. All the wiring was done 11 years ago when this room was frame. The wires are all inside the walls and it all goes to a closet where the equipment is. My front ceiling speakers are set up for 5.1 and would have to be moved to proper Atmos position. Plus I would want floor speakers for rear surround and that would also be tricky because of the wiring. If I just did 5.1 I would probably continue to use rear ceiling for surround and then there would be no cost. It would just cost a lot of money for speakers and installation 

From what I’ve heard from people who upgraded from 5.1.2 to 5.1.4, even those with entry-level systems, I’ve seen many state that 5.1.2 -> 5.1.4 was a larger jump than 5.1 -> 5.1.2.