In the screen that pops up after you have cleared a challenge, I’d like to see an option for rating the difficulty of the challenge. As things are, the only place you can do that is in the info page of each challenge. If you want to rate a challenge you just cleared, you must click on “challenges”, navigate to the right page, click on “play” for the challenge you just did, scroll down, rate it, and then going back to challenges to find the next one to play. Repeatedly clicking “back” in your browser works as well, but my point stands that people are more likely to give difficulty feedback if they can do it immediately after solving the challenge in a convenient manner which doesn’t require navigating away from the cleared screen before going on to the next challenge.