Really nice looking cabinet and grill colours. If you don't already, you might want to pull the vp100 out a bit during play so it hangs over the lip of the shelf it is on by a little bit. That way you avoid boundary effects.

Have you experimented turning the surrounds 45 or 90 degrees from flat against the wall? Just curious what positioning you have found sounds best. I might be changing the room I have my HT in and have to also put my couch flush against a back wall like you.