you're on to something!
One problem I see, probably common in software engineering, is that in many apps the explanation on relay settings does either not exist or it's written in developer language. Most of us nerds kinda get it or spend the time to figure out what's needed but my sisters jaw literally dropped when I recently tried to show her Amethyst. She loves the client but I could see how her brain went blank the moment she looked at the settings. I don't think she has looked at it again since then. I'll ask her over the holidays. 

So yes, certain features should be auto-configured initially and also better explained within the app. Relay indexer sites should add relays to tables with "feature ticks" (so should clients that recommend relays). If needs to be clear to the user where to use certain relays and where they shouldn't be used. For example, paid relays in the inbox config - your friends cannot write to.