Chris, I looked at your pictures and it isn't apparent why you say that you can't place QSs. At worst, even if the side surrounds couldn't be wall mounted, they could be placed on stands in a similar position to what you do now. The wider dispersion of the QSs would be of particular benefit at such close distances.
As to the 6190 and the rated "4 ohm" impedance of the M80/VP180(more realistically about a 6 ohm average, considering the overall frequency range), it would handle them easily at 95dB, which would use only about 10 watts at most at your listening position.
