Upgrading from Primaluna

How much heat can it possibly make? Is it appreciable enough to even worry about or to make much of a difference in room temp? I own a class A Amp that gets quite hot, but I mean I'm not sitting on top of it or near it. I use it year round...no idea why some make this an actual issue..it isn't. 

" 10ft width and 15ft length so 6ft between speakers and 2 ft from side walls is all I've really got."

With not much to work with other than it is a dedicated space, it suggests almost nearfield setup and those Sopras need to be pushed out 4.5ft away from the front wall, and your already sidewall is near "right"(depending how your measuring)it's actually CLOSER together.

http://www.cardas.com/room_setup_calculators.php

Using the 1/3  it would be around  5' or Cardas calculation above. You should have your chair distanced accordingly.

Rack needs to go either behind you or somewhere on the side.

Depending how those speakers react THEN, is what you're faced with. The DSP thing with a mic to "tell you" what your ears are "missing."  wouldn't invest in anything until you compare results and consult with the room acoustics companies.

You have a Sopra 1 and subs room perhaps to some. IMO, you still will  get the Sopra 2's to "work."

How loud do you like it playing?
If you are not playing it loudly and clipping, then more amp is not going to do a lot.

You might have less distortion. Whether than matters or not is a different question.

Ignore any of the posts that are off topic. Your question was about maybe trying a bhk essentially, I say maybe build a short list of more powerful amps both ss and tubed and find a way to try a couple. Those other posts are full of assumptions.

I think you could benefit from moving your speaker outwards and revisit your front end components. Maybe even going to a speaker that fits your room better.