Good question. I would also like to find which is the better way to do this. I would like to hear other peoples recommendations and comments on this. You may already know about this site, but it talks about setting up different depths in the stage.
Of course I know this wonderful site, what a gift ! I started to experiment reverb combinations after reading these tutorials.
Yesterday I left Sir (mono-to-stereo technology) and switched to Pristine Space (stereo-to-stereo technology) which makes a big difference in the final result.
So I applied 3 combined reverb and the mix gived more clarity and crunch. The delays used (and provided by DpDan in some thread) were about 10 Ms for strings, 17 Ms for woodwinds and 25 Ms for brass and percussion.
The question about dry versus onstage reverb settings remains appropriate. Perhaps someday Bruce will catch this one and elaborate some thoughts in the Virtual instruments magazine