EURkey seems to work particularly well for German [0]. I wonder why such alternative keyboard layouts have not caught up a bit more. Problem it is really hard after 30 years programming ( and using vim) on German keyboards (which admittedly is a pain) retraining my muscle memory.

Edit: EURkey seems to be pretty much the altgr-weur mentioned in OP

[0] https://eurkey.steffen.bruentjen.eu/start.html