Attached herein are resources for a simple (not to say primitive) mod of the v5.0 default theme with separators and empty spaces, borrowed from:
Default 5.0 Nitpicky Edition by Lokasenna
Defaultwithmorelayout_4-sc2px by RenoMellow
LCS Default 4.0 by lucas_LCS
AND
Abhi Modded AM JANNE 2017 Ctho_Mod by Ctho2017
First make a backup copy of the default theme, just in case
Then simply drop the enclosed folders and the rtconfig.txt file into the default theme main folder Default_5.0_unpacked (accessed with WinZIP or WinRAR for those who're not in the know)
Tip: Muting a track before converting it into a separator or an empty space (or afterwards via Actions) creates a nice dark strip across the arrange canvas which aids visual separation of the arrangement blocks. Can be set up with a custom action, similar to the one referenced in the tutorial at the link below
A tutorial on how to create separators in both TCP and MCP in one go using layout slots
https://www.youtube.com/watch?v=KaOH_m4tHGg
Alternatively, to spare layout slots, which might avail for other purposes, it can be done with SWS extensions Auto Color/Icon/Layout, a SWS ReaConsole command cycle action and a regular custom action whereby a newly added track is automatically assigned a name 'separator' (or any other as long as it's consistent) to be then assigned a separator or an empty space layout based on the rule set in the Auto Layout panel
Auto Color/Icon/Layout config
Color could be added as well
ReaConsole command cycle action
Custom action
The highlighted steps are optional, the last one is the ReaConsole command cycle action shown above. 'Lock track height' script is irrelevant for the latest build, in previous builds it forces the track to maintain height during vertical zoom-in while the cursor is over the arrange canvas which is achieved with the script "JamesHE_ReaVertical Zoom non locked mousewheel".
To turn an already created track into a separator the ReaConsole command cycle action alone will suffice.
The custom action doesn't affect regular track addition by double click or via regular menu option.
In the MCP label text orientation in separators which have it can be changed in the Reaper Preferences under Appearance by ticking the option "Draw vertical text bottom-up", a tip I came across at
https://forum.cockos.com/showpost.ph...71&postcount=7
UPDATE
Managed to make the separators' labels centered regardless of the vertical zoom level.
A summary of separator types: empty space, blank track/channel/strip, with and without labels, MCP separators of various widths, including channel default width to be used in a track inspector setup as suggested by Hopi.
One point for improvement is the color of the label placeholder in an expanded separator as a visual aid to quickly locate it with a click for entering a text. At the moment it may take a few blind clicks around the center until you hit it.
If however it's created with a custom action described above, there's no problem as the text is entered automatically, then it's just a matter of changing it.
UPDATE
In two TCP separators made the label placeholder color differ from the background so it's immediately locatable for keying in text.