An FDroid desktop client that adb installs APKs would actually be lovely. I pretty much exclusively use FDroid, but I gotta say I unfortunately find all their frontends to be rather buggy and with very little user feedback when things break (repo updates are hard to observe, downloads hang, updates mysteriously fail)
I feel you about the frontends being buggy. Right now I've settled with Droid-ify[1] for doing my F-Droid browsing.
[1] https://droidify.app/
Droidify sometimes does a weird thing when installing apps:
1. Ensure Droidify is not running. 2. Launch it. 3. Tell it to install or update to an app. 4. Receive an Android system prompt to approve the install/update. 5. Approve it. 6. Tell Droidify to install or update another app. 7. Reveive a system prompt to approve the action of step #3 again. 8. Approve it. 9. Receive system prompt to approve step #6. 10. Repeat #6 through #9 for more apps.
Workaround: Do steps #1 through #5.
Foxy Droid doesn't have this problem, but won't auto-download updates for you.