I have never heard the Sonus Faber, so I can not comment on the differences you are hearing. I am just a little surprsied. I wonder if the warmer feeling is coming from the intrinsic sound of the sonus faber enclosure. I can not "hear" any contribution from the cabinet in the wilsons.
From looking at the limited pictures you have posted I would agree that your room is probably a huge part of your problem.
As for integrating your sub with the sophias, I went through the same thing with my sunfire signature sub. Once I had completed adding all the rest of my components (bigger amp and dedicated pre-amp) I found that the bass was outstanding and the use of a sub became unnecessary. Actually I found the bass of the Sohpias to be much quicker, tonally correct, and more truthful to music than the sunfire could provide. And damn do they go deep. The sunfire only added loundness and robbed the sophias of those great attributes. I would recommend fixing the room interactions and keeping the sub for your home theatre only.
I would be very interested to hear how the Lamm's sound with the Sophias. Have you heard hem on the Sophia's?
