I'm not so sure it should be written off so quickly. Ideas have been exchanged and questions presented. Doesn't mean it's not doable, just may take some more thought to keep things current or relevant.
I can see why "hobbyist" devs don't want to be subjected to a rating system. Get a few people that don't understand how the apps work,or don't take the time to work with the dev or community to figure it out and it won't be long before a good dev gets completly trashed for no reason. Think about the times you have seen a one or two star rating. How often is it really obvious that who ever wrote it had no clue what they were doing and trashed the subject as a result. Maybe using update dates may be an option? Just spit balling. It's an intriguing idea, worthy of discussing further.