I've got the MV4 in my live rig but don't really use it, I still have my original Quadverb set with some mild stereo delay and reverb. Been quite a while since I bothered with other Fx, in my studio rack I have a TC MOne XL, again just some mild delay and reverb. When I put the MV4 in the rig I had intended to possibly run up some patches with it e.g. flange, bigger delays etc but never bothered
. A G Major would be a good addition for you IMHO. My mate MikeB has a GMaj2 and gets some great sounds from it and also some CC control. He's coupled it all with a Behringer FCB 1010 midi pedal for the midi control, I use the ADA MXC with expression pedal and Quad switch which maps very nicely with my MP2(s).I'd go at least a 4RU case (well I'd kind of need min 6 RU, but my rack is 8RU and I have a small mixer velcroed to the bottom, but this includes poweramp (currently Carvin DCM 200L, 1 RU) (So MP2, Quadverb, MB1, MV4, DCM200L, mixer...)
Anyway, seems it's time to grow a rig