Clients just work, no matter what I have tried with the jellyfin client on android tv it always fails on first or second load up, also subtitles never quite work as smoothly as they could.
You can download movies or tv shows from your library so you could watch them while without internet, nice for road trips or flights.
Also I use https://trash-guides.info/ for all my setup for subtitles and no matter what I tweak they just are always a little off with jellyfin, no so with plex.
https://docs.linuxserver.io/images/docker-swag/
I would tell you to entertain swag, has a lot of pre-built configs and has some integration with crowdsec and docker mods.