Do you have any seat off-axis; pretty much anywhere but directly in front of where the center would go (if I want to be overly simplistic)?
I'm not a fan of bi-pole etc. for surrounds. I prefer monopoles for surround duty. Preferably with good off-axis.
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Subwoofer?
Honestly? Not a god**** thing. Bright generally means overemphasized high frequencies, but nobody uses it that way. Don't pay attention to that nonsense. People call audio stuff all sorts of silly terms. Chocolatey, warm, bright, laid-back, hot, cold, etc. I'm waiting for the days we describe speakers as "horny". At least that would be fun!
"Dude ya gotta hear that speaker, it was so horny!"