Just had a bit of a play with Ardour. The busses and tracks, effects, etc. seem to make sense to me. Seems a bit like my mixer only with Ardour has more buses, routing options, etc.

Using alsa_in, I just had it recording from a ZoomH4 and a Yamaha mixer at the same time.

Not that I'm planning on getting one, any idea what the Lexicon Omega which looks as if it can do 4 mono tracks from one device is like.