Other jammers have already stated some good points that should work. For a more “utilitarian” approach to receive more high-quality feedback, when you are browsing the submitted games, you should look into the review section and see:
- Any reviewer that provides in-depth feedback on the game
- Whether the developer replies to their reviewers with self-reflection
- People that do both (You can click into their profiles and see their comment history)
If you play and give deep feedback to their games, these kinds of people will likely do the same to yours.