Definitely try running a full Linux distro with it, it's pretty fun and a self-rewarding task, even if you don't end up actually doing anything with it. But you may still find it useful in some ways, for instance, you could run a full fledged desktop Firefox with support for ALL addons, use it to inspect and debug web pages etc.
And if you feel like it you could take it a step further and install Zink and Box86 to play Windows games.
Just as a tip: you can run every Add-on on Firefox nightly. You can add your own add-on collection and select from that.
You have to go into dev mode though. Yo do taht by tapping the Firefox logo in the about section like 5-10 times.
You have to have a Firefox account though.
Or you could use my fairly small add-on list: