Quote:
What I was trying to do was get the real musicians to play the tracks in the midi file but maybe I should just
convert the midi tracks to audio then load them into my DAW then assign better instruments to each track from there.


I think you may have it backwards.
Once tracks are audio, getting them to act like a MIDI track will be problematic.
If you can export MIDI from BiaB then you can assign different synths/sounds .. but once they are audio probably not.

Some Realtracks include the MIDI transcription, and if they do you can change the synth/sound, but once they become audio it becomes much harder.
(exception may be using Melodyne, but still much more difficult)

I do not work here, but the benefits are still awesome
Make your sound your own!