I can whole-heartedly recommend setting up a zandronum (doom) server with Brutal Doom installed for a really fun classic-but-up-to-date FPS experience, I played this regularly with friends for years and we weren't even born when doom came out, it genuinely is awesome.
Only issue I've had with Signal in the past is sync between desktop and mobile, is this still as bad as I remember?
In a way I feel kind of responsible to be more active to promote the community more. I want this to succeed and it won't without content, so I probably will end up being a lot more active than I used to be on reddit too
I've installed Jebroa but it seems to be a bit fucky for me, (Pixel 6, GrapheneOS ROM which probably doesn't help), hopefully it gets better with time. Gonna give thunder a go