Linux Doom Launcher is a simple GZDoom mod loader for linux written in python using the GTK toolkit. It supports loading up to 3 PK3 or PWAD files, so you should be good to go in terms of loading most of your mods. As I've gotten tripple mod support working, I'm going to focus my efforts on expanding the features of this program, and eventually it should be fully featured. It depends on GZDoom, so make sure thats installed on your system, and not the flatpak or snap package.
Here's a couple screenshots of LDL.
Before creating an issue, please check TODO.md. If what you want to open an issue about isn't there, go ahead! If you want to tackle something on the TODO list, feel free, just open a pull request once you've finished working on it.