You can have as many windows maximized as you want. There's not upper limit to maximized windows.
> Those are undiscoverable and should not be the only option.
Just do `<super> + appname` and you'll jump to the window in question. No discovery required. The WM will do the discovery for you.
> Shoulda, coulda, woulda. I manage with the programs that are, not the ones that could be. I'm not interested in developing my own DE, not redeveloping all the other programs surrounding it.
> One isn't even a GUI application. The second sees regular use with a GUI, but only for reconfigurations that take less than 10 seconds.
The not-gui application you could put into a user-defined daemon (check [0] on how to create user services). The GUI-for-reconfiguration thingy you can put on a workspace, then it's out of your way and still accessible for reconfiguration.
> Why would I want to relearn a new UI for only marginal benefits?
To be snarky; "Why would I want to relearn riding for a new horseless carriage with only marginal benefits?"