Psychologist by training, production planner by trade. I started using Linux around 15 years ago on my laptop. My self hosted journey started with a Chromecast plugged in a TV and I would cast file from my laptop. Fed up on how laggy and buggy the set up was I installed Kodi on my laptop. Then, I bought a SBC and a few years later a refurbished NUC for few bucks.
I now selfhost around 10 services but nothing too complex (jellyfin, grocy, paperless, etc). I know how to set up a docker image and thinker a bit with config files but I rely heavily on guides for tasks more complex than that. There are a few services that I would like to setup but as I get older I get less joy from setting up a system than using it and the hours I can invest on this are unfortunately limited.
There are tons of it, it really depends on how much time are you willing to invest to set it up vs how many features you want. Taiga, kanboard and leantimes are all viable alternatives. My best bet would be redmine, with a couple of plugins it can provide everything you need and more. I don't think there is a single docker container but there are a couple of prebuild VMs that we used successfully for a while and on the plus side is no feature are locked behind some subscription model like other powerful alternatives.