It’s an amazing tool.
For your comics list, I’d suggest Dataview, quickadd, and templater plugins. With those three you could easily make a database with an entry mask, that automatically sorts the files into folders and sets metadata based on the mask input, and dynamically creates various tables for reference.
Folder notes could be useful too, depending how you want to set it up, and how detailed you want to have your tables.
Whatever you decide on, good luck. :)
As others have stated, grapheneOS is a good choice, and it’s extremely secure.
Another option is murena’ eOS. If you live in Europe, thier store sells phones with the OS preinstalled, and if you don’t, the easy installer app works pretty well with most models.
But fair warning, I recently installed eOS on my wife’s old Samsung S7, and I ended up having to do the installation manually with adb (command line tools). So read up on the phone you want to use, some are easier than others.
The operating system itself is great, and allows for anonymous usage of the play store (free stuff only of course) as well as F-Droid out of the box. You can also add your Google account to get full play store functionality, but then Google starts getting your info again, albeit less than with standard android.