Generally speaking, I've had plenty of luck posting my games to game-development subreddits. Users over there are more than happy to suggest features or provide feedback to games; someone was kind enough to make a video about one of my games. Specifically, I recommend posting to https://www.reddit.com/r/playmygame/ and https://www.reddit.com/r/WebGames/ (if your game is playable in-browser). Hopefully, this helps!