I bought some Owens Corning 703. Now what?

@amtprod It’s a good question, but what is not evident from the diagram is that the right speaker, nearest the bathroom wall, actually fires into the entrance way which forms part of the front wall. In other words, there is no first reflection point (as revealed by the mirror test) on that wall.

I went and measured differences in the room. In actuality, my right speaker is 12’6" from the right wall and my left speaker is 15’ 3" from the left wall. I’m not sure that the difference there (3’3") is enough to cause a big difference. Both are far enough way to not be able to smear the direct speaker sound reaching my ear from about 8 feet away.

I will try your test. Yesterday, I did put my panels along that bathroom wall just to see what changed, and there was no apparent difference. Again, because there is no first reflection point there, so that is probably the reason.

@chorus Thanks for your suggestion. Ceiling seems crucial!

@hilde45  Oh I see.  Yeah from these measurements maybe there isn't much if any reverb/cancelling/smearing from the asymmetrical room layout (to some extent).  Try the test anyway, just to see and maybe it will help identify other sonic issues as well. 

Hey @hilde45, good post ... the first report-post shows that you have identified two symptomatic areas in the mid to high frequency range.
As another experiment you could double-up panels (2 x thick etc. gives double the bandwidth, roughly) and extend absorption lower. 
The ceiling should be a deep panel (example 5 inch depth), with long narrow panels-spaced at different lengths apart to gain a baffle effect.
400 - 4000 wavelength range (3 feet - 3 inches) will likely need the most attention other than bass.
A Tube Trap(ASC) would go a long way to tame bass and help with mid to high frequency.

Thanks rego and amtprod. I'm going to try those ideas next!