Acoustic treatment for apts

I'm hoping I could get some advice for my odd shaped apartment. I've got all kinds of acoustic problems. The right wall has a fireplace. The left wall has a V-shaped indention. The rear has open spaces on both sides with a big one on the left. The ceiling is vaulted, but slants left (high, 12') to right (low, 9'). My acoustic reflections don't have a clue as to what to do. Neither do I.

I've been looking around and found some nice acoustic panels I could hang on the wall in the 2" & 4" variety. There really isn't a good place for a bass trap. How effective would this be? I've got great real estate in the front and rear. Your ideas and suggestions would be greatly appreciated. I can modify anything, so long as it can be reverted back.
Pretty clear you should have the speakers from one side to other instead of the long way.
By having them each side of fireplace? you can solve plenty of the issues you would have if you tried using the long direction.
How WIDE is the space between the Fireplace to your "V" dent
10 feet?
14 feet?
12 feet it would be fine/.
even ten feet could be ok.
eight feet and it gets kind of tight, with having a chair in there and all...
The ceiling would be fun if you had your speakers at the fireplace sides..
You could have the other equipment anywhere away from there.. just have to have long speaker cables...
Well, there's a problem. First, I want to go over the layout so there's no confusion.

The living area is almost a cube in actual dimensions. From my current front to back, there is an extra 10". The distance between the fireplace and V-dent (sideways) is almost 15'--which is more narrow than the other way (lengthwise). However, given the extra space I leave so you can walk behind my listening chair to the sunroom (lengthwise), it makes the room a cube in terms of physical positioning.

It is impractical to place the speakers on either side of the fireplace (sideways), which could possibly help acoustics, but there would be no place for my 50" TV. Any other way, and the equipment will get in the way of the natural pathways of the room.

I can hear phase problems due to reflections. This I'm familiar with and sensitive to. My goal would be to deaden the entire room but I know that's impossible. My goal is to see how close to dead I can achieve while retaining some semblance of style and neutrality (i.e., not a man cave).
Do you personally know a good, high end dealer that works nearby?

They might have the time to come over and give a quick assessment. You sound like you're half way there. They might see something that's eluding you.

All the best,
Google GIK they have a lot of info on room acoustics on their website. Good Luck