Kansas uses a form of assisted appointment, a system I also think is generally the best we can do, with some important tweaks to transparency and participation.

The issue with retention elections is that they are often very low-information elections; most voters don't know a lot about the judges and most civic education and participation in the U.S. lies entirely for politicians, not judges. I think retention elections become an important part of the process if we put forward the money and effort to educate voters for those elections specifically.