[joachim]

I use 10 mem locs of the type "Time Properties - None" to show/hide specific food group tracks (Dialog, Music, Atmo, Fx Mono , Fx Stereo , ...) and store their track heights.
Some may have a connection to a window config, but mostly their function is to "bank" certain tracks.
Those mem locs are defined in a template, further ones can be reserved by empty markers of the same type "None".
Since they are "Time Properties - None", they are either on top of the mem loc window (not sorted by time) or on the bottom together (sorted by time), apart from "Marker" mem locs.
Their names always start by "View" (View Dia, View Music, ...); easy to differenciate from those "airplane-noise-working markers".
Since the mem locs 1-10 already exist, a new working marker with "Time Properties - Marker" would have the number 11 and following.

Pure window configs, that's the job of the window config window, in my eyes.

For scenes, I use a midi track, with empty clips for each scene; labelled with the rough content of the scene ("Driving to Town", ...).
Those clips can be accessed in the clip list, with only Midi shown and sorted by time easily.
They can be colored in the clip list and in the midi track (all scenes with "Tom+Martha" in blue, all scenes in a forrest in green, ...).
So, all scenes are in a separate list and not in the mem loc window.
The mem loc window is clean and reserved for banking mem locs and working mem locs when going through the mix for adjustments.
Works for me, open to discussion.
Would be glad to get to know other workflows.