Petty whines re Themes and colors

I know in the scale of things, these are small matters, but I’ve spent a long time not writing but procrastinating by doing this and feel like whining.

I have 3.1.2 on my MacBook Pro. I saw something here about Themes, and tried the ones in the program, just for the heck of it. When I went back to Default, I lost some color preferences, which were all fixable, except: I keep the Inspector open and usually to Bookmarks. I had the top pane, which lists the Project Bookmarks showing a color of my choice. I did. I absolutely did. And I’ve been through every Preference setting there is and can’t find a way to restore it. I can get the icons of Research files I’ve put there to show their label color (at the cost of dulling the icons in the Binder), but that’s all I can get. Everyone of those listed Bookmarks were light purple before, not the icons, the whole whatchamacallit with the document name.

So, frustrated by that, I decided while I was fiddling with Preferences, I’d do my own Theme and did. And spent longer than any not OCD-inclined person should have doing it. Used a novel I’m working on to get every color the way I’d like, saved the Theme, and thought, “There. I’m happy with that.”

Then I opened another project and invoked my new Theme, and guess what? The colors are different. Not that blue isn’t still blue, but on the one I set up as I liked, the colors are nicely muted, and in the one I used the Theme on, they’re annoyingly bright (Binder, Outliner, Corkboard, basically the label colors as background).

The problem seems to be Opacity of Label Color when used as background. So I can fix it, but when I do that, it changes for every project. The one that was right becomes washed out when the one that was too bright is where I want it.

Is this Theme thing a kinda sorta? Are there fixes for any of this?