I’ve looked at a few on fdroid and they all seem like they aren’t being maintained anymore.
Edit: I’ve spent the past day trying most all of the suggested keyboards here and I think I’ve landed on either Unexpected Keyboard or AnySoftKeyboard. Thanks for all the suggestions. Thumbkey is quite the thing to get used to.
I use AdGuard and do the same with its built in Firewall feature for GBoard. The thing is, since I don’t use custom ROMs I can’t be sure that GBoard won’t just use Google Services for spying/tracking.