@Tutanota Couple others:

News: Any RSS apps (eg Feeder)

Wallet: Not great options. But loyalty cards work in Catima. NFC payments are tricky. Some (non U.S.) banks... and Garmin Watch again...

ToDo: Tasks.org, jtx Board

Weather: Breezy Weather

I'm a dummy. I just remembered.

SmartWatch (again) : Pebble! They're back!

@Tutanota a few suggestions:

Email: Proton (yes yes I know, but you mention them in calendars anyway.)

Translate: DeepL (?)

Browsers: I know they're Chromium, but options like Vivaldi and (reluctantly) Brave aren't half bad.

App Store: Obtainium

Android: Drop Calyx, its not actively being developed right now and is more of a security hazard than anything.

Maps: HEREWeGo (HERE Maps) is honestly pretty alright.

SmartWatch (WearOS): GadgetBridge, Garmin(?)

Google Home: Homeassistant