I suggest you create a system which selects top users according to the evaluation of the uploaded works. Add a category in components section where you can filter all those uploads and group by "Most likes" or something.
And also you could give extra points for the uploaded works. And those points could be spend to buy something (stickers, t-shirts, etc.)
The main point is-to motivate users to be more active and there will be more choices of uploaded custom works by users to choose from.
Interesting concept. I personally would love to see the ability to filter "out" the components that we "DON'T" want to see anymore. There are so many people uploading/sharing sub standard or just basic things that are easily done ourselves without a pre-made component as well as a ton of things that are all fully "Custom Code" and shouldn't really be in there in my opinion, that I would love to be able to tell the app that I am not interested in and don't want to see that particular one anymore. A way to "Hide" them would be great!
Don't get me wrong, I appreciate shared components, even if they are custom code completely, but that's something we could do here on the forums rather than filling up the Components list with them. I use plenty of custom code items in my sites so I truly do appreciate those shares, just not in the app. :)