Marshall
Am I better to do all my midi work first, and only then select separate outputs in AD2 once I am happy with the data I have input? Is there a better way to work? I think I am missing something.
In answer to the above Bill I would say there aren't many reasons to start bouncing down your midi tracks to audio until you're ready to produce your final mastered track.
I would certainly never bounce down your drum tracks before your completely happy with the midi tracks themselves.
Some people will bounce their drum tracks down once the midi is finished so they can process each individual drum track separately and use whatever effects they have.
Many will do this because they're engineers (or used to be) and this is what they have always done, some will do it so they can freeze the VSTi and thus save system resources.
Those are really the only reasons I can think of for using that method but today's DAWs are more than capable of handling the strain and with VSTi's like BFD3 or Superior you can route individual kit pieces to your sequencer to use whatever effects you have and so I don't see that as being particularly necessary these days.
Another reason to bounce down to individual drum tracks would be when you're sending your songs to be professionally mastered they will most likely want separate drum tracks already mixed with effects printed so they can master them and tweak them if needs be.
I keep all my drums as midi and don't bounce them down until I'm ready to bounce the final mastered mix to upload on line.
Steve