Filtering shows by imdb rating (and other similar sites).
When I hear about a new show, I always check the imdb rating, and if it's below 6, I know it's not really worth watching. And sometimes I stumble upon shows I never thought I would watch based on the genre, but with an imdb score of 8+ I give it a go anyway. And often I am surprised.
If gathering rating from other sites is too much work, how about using your own rating for tvmaze-users, and use it as a filter? :)
Your own rating isn't really used that much atm., but perhaps giving it a purpose can expedite things and users will start rating. :)