It would be great to be able to create more than one marker track and have them organized/subdivided alphabetically. eg:
MARKER TRACK 1 (a): 1a., 2a., 3a.
MARKER TRACK 2 (b): 1b., 2b., 3b.
MARKER TRACK 3 (c): 1c., 2c., 3c.
Marker Track 1 (a) would always be default for keyboard hotkeys, but you could switch that to b, c, etc.
Or, just having Marker Track Versions like the other track versions.