This is a good approach. I would not even use Izzy’s repo shown by OP (at least not on a daily driver device - great for testing newer apps I’m sure) because I don’t see it as advantageous to get updates so quickly or access to apps that are not yet (or will never be) fully open source.

Basically I see most of the value of F-Droid in their build server and official repo. So I only add repos with a very short list of apps, like microg and KDE.

I can always install the odd apk manually, or use Aurora store (preferably in the work profile)