They could do with an option that restricted timeline tracks to only accepting matching clip types but personally I prefer the Adobe approach.
My Avid sequence template (stereo deliverable) is 2xmono & 2xstereo tracks for dialogue AND effects (and 2xstereo for music) = 10 tracks, and goes up from that.
In PPro I start (and usually stay within) 2xstandard for each = 6 tracks. Much more manageable PLUS I get sub-mix tracks!
The timeline indication (e.g. speaker icon for mono tracks) is pretty clear and there IS track labelling per clip in the timeline so I don’t see it’s too hard to unlock. Problem is more at the editor level, too many editors have no clue what they are doing with audio in either program. I see it in avid with weird panning and audio tracks with no discipline and in Premiere with the track mixer set to bizarre levels. There’s just more you can screw up in Premiere, but please don’t encourage the dumbing down of the tools.
With the caveat that I’ve not had to export an AAF from Premiere yet – the AAF implementation of exporting mixed source clips makes a lot of sense. Given 1 standard timeline track with mixed stereo & mono sources it will create 3 tracks in the AAF sequence 2 for stereo clips, left & right, and 1 for mono clips.
What would be useful would be a couple of things Avid offers. Firstly a ‘.exported’ sequence showing the sequence as contained in the AAF. Second would be a ‘split to mono’ option to help those wanting to work with mono tracks.
But most of all Adobe need to copy ‘head/tail fade’ and ‘add transition in to out’ from avid.