I have in the past compressed reverb sends to smooth out responses in the reverb program and to avoid transient slapbacks and things. I've compressed reverb returns to bring the reverb tail up more "in your face" and even sounding without increasing the reverb level.
It doesn't hurt to try. Are your wet/dry mix parameters set all the way wet for the return? Have you checked phase? It sounds like that may be a problem.
_________________________
Current live rig: Roland RD700SX, Hammond XK-3 with Leslie System 21, and Muse Receptor. Also a Nord Stage 76 other times instead. And a Roland FP-7 for jazz gigs.
HOME: Kawai MP8 + a bunch of VI's.