IMHO
1.Definitely get rid of that sound bar. Get matching LCR.
2. Upgrade your sub. My living room is similar to yours and I bought a SVS PB12-NSD in their outlet for $450 ( great sub for that price, )however I had a bass null, so I called SVS and they recommend I get a 2nd sub, a PB3000. I wanted to get a PB2000, the PB12-NSD is the older version of the PB2000. So I was committed to a budget of $1300 and I started shopping around and came across Power Sound audio and gave them a call. Spoke with Tom V ( he is the V in SVS) & he is a wealth of knowledge. I ended up buying a One V1510 and sold my PB12 and my bass null is gone!
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