Agreed, or at least an output level bar graph so you could get pretty close without having to dial up reference rigs and go back and forth. Ideally with different ballistics and peak hold times to get a feel for RMS vs peak.
Yes I was also wondering if there would be a system to facilitate this. Now with the new "morph" function, I find it increasingly hard to adjust the volume of the new morphed rig due to how many variables now affect the final output (raising the gain, adding compression, putting a pre-stack pure booster, etc).
Also, I would love if some effects (notably the Green Scream and compressor) be completely transparent at 0% mix so that we could use it in "morph" from totally transparent to something else.