According point 2: I choose homepage over Heimdall. It has more direct integrations (e.g. Homeassistant, Synology, Paperless-ngx, Warchtower…) where you can display specific information directly on your dashboard. It is easily set up by a couple .yaml files. You can find lots of examples online and in the documentation.
Start with Docker/Containers.
Once you understand the basics of it you can start selfhosting all sorts of applications from/on your laptop with very little effort. For Docker Command Line Basics there are tons of free tutorials online. If that’s to big of a step in the beginning, start with a Portainer (spinning it up is basically just copy and paste one little command) the rest can be done from the GUI. Docker will also help you to figure out what you might think is worth „selfhosting“ for yourself. Because selfhosting is almost like clothing: Everyone has their own taste and style.
I would agree that curiosity is the biggest driver here. A while back I played around with kali and aircrack-ng and was eventually able to crack one of my neighbors WiFi (big city - lots of signals). Even entered the router which was set up with the “standard credentials” of its type. But in general it’s very unlikely that you will successfully crack any WPA2 Wi-Fi signal. If you want to crack a specific signal it gets even trickier…
For automated container updates I can highly recommend watchtower. It also works with updates for specific releases/versions where you’re not using the :latest tag. It was also relatively easy to configure for my small setup of 15 containers.