The way you are setting up your I/O is similar to what I do in my setup. I set up an AUX for each "stem" that I want to process. In my world, that might mean that I have a stem for Strings, a stem for Beats, a stem for Brass, etc. Let's call these "stem auxes". I then route each audio track to one of these stem auxes. I have separate reverb/delay auxes for each stem, and I route those auxes to the stem auxes. Finally, I route each stem aux to an audio track (if I want to record them to audio) or a master aux if I'm just going to bounce the audio.
There's another layer of complexity in my setup. Sometimes I need to prepare a stereo mix and a surround mix of a song/cue. So I actually route certain tracks to MULTIPLE auxes. For example, I might route my Beats stem to a MASTER STEREO AUX or a MASTER SURROUND AUX.
This is all getting quite complicated! It might be worthwhile to write-up a description of how I set up my I/O as a MacProVideo blog entry. Rounik, what do you think?