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What is the height of your room?

Are you planning to place along the length or width?

In case of width placement you can partition your room with curtains and have advantage of saving on smaller speakers and smaller amps. Circular partition would be my advise. 

Speakers can be around 7...8 feet from each other and nearly same will be your listening position from speakers.

In this situation, the choices are extremely many from lower to higher powered options.

I have exactly room half of your room filled with B&W N803D/Cary CAD200 dual mono amp//Mcintosh preamp C26. Feels like slight overkill to the size of the room. The bass in these speakers isn't their strongest part, but controlled defined and liquid. 

Ceiling 9 feet

The great thing about a car listening system is that you are always in the sweet spot and it’s perfect for surround.

  I suspect it’s the surround system that has you entranced.  I would work with a good dealer to see what is possible in your listening room.  I use a conventional 5.1 surround as Atmos isn’t feasible due to low lying ceilings.  If you can swing a couple of height speakers you might enjoy it

Headphones would be the best way to recreate the sound you are looking for.