I am not a lover of D'Apps. for the main left and right speakers. I have a pair of Old Garrards that I tried in this fashion. I just do not think they were "right" Now of course this may be dependent on the positions of these types of speaker relative to ear level which in my mind would take some real experimentation. To confuse the issue of the SVS is the fact that the tweeter of the left/right speaker is a design that is not in line with the woofers as many D'Apps. are. The photo shows the tweeters facing towards each other on stands. You could call this a mirror image. I would switch the L/R speaker to see if they should be more opposite each other. Again this is a mirror image. The problem I have with mirror image of these types is that to my ears the phasing of the speakers or the whole surround system could be out of wack.
There is another factor that I never seem to hear of anyone testing. What wiring scheme is used in those speakers relative to the woofers. Some clowns put 2 four ohm speakers in series to make 8 ohms. This could make an awful sounding L/R speaker. The right thing is to wire two 12 to 16 ohm woofers in parallel. Your impedance will be 6 to 8 ohms and your speakers at the very least will phase correctly with the system. Fortunately those old Garrards were wired the latter way and have made a good center channel speaker for my system.
