I was playing around with our SQ7+ and SQ5+ and discovered that you could route the FX and Ultra FX returns to outputs (local/SLink/I/O port). I then set the FX/UltraFX busses to pre-fader. What this means, is that we can now utliise these busses for additional aux busses for foldback/IEM mixes. You can gain 4 mono busses and 4 stereo busses giving you a total of 4 mono and 16 stereo discrete mixes on the SQ+ series. In order for this to work, you need to assign an effect to the FX buss from the FX racks. I used the DynEQ4.
Having done this, it would be useful to be able to have an add-on that has 6 bands of PEQ (w/ bypass switch) and a RackUltraFX add-on wtih FBA.
I hope you find this useful.