Sprial Knights is a great game, but there's just not enough content. By the time you reach tier 3, you've seen every level at least once, and most of them you have memorized to the point that you know that that button will open the gate, and going over to those treasure boxes will spawn monsters. What the game needs is more content, but with the SK team being really small, and mostly focused on creating brand-new content (boss floors, new creatures), how can we get the level diversity the game so desperately needs?
Community Levels
The idea is simple: OOO releases a level editor. It doesn't have to be anything fancy - it can simply be the tools OOO uses to make the game, regardless of how complex it is. OOO would put up a submissions page, much like TF2, where players can submit levels they've made using the editor. OOO would pick out exceptional levels to add to the game, giving their creators CE and some sort of cosmetic armor (This could be done a few ways. Either one single item, or multiple items (1-5 stars) each one slight different/more awesome, and you get them in order as you have your levels accepted).
The best part, is everyone wins. How so? Let me explain:
Why OOO Wins
Why this is great for OOO should be obvious: they get tons of content added to their game, and the only cost to them is the time it takes to polish up the editor and set up the submission system. This is significantly less work than actually making the content themselves, and it frees them up to focus on new enemies/environments, as the community will be mostly fleshing out content for existing environments.
Balance on these levels isn't even a problem because you just choose balanced levels to add to the game, or modify them slightly before accepting them. This especially true if you're just supplying players with your actual game tools, as opposed to some in-game system (like CoH) which would have to have all sorts of crazy restrictions to prevent abuse.
It's not even a gamble, as TF2 has proven that it works, and that it works exceptionally well, as the vast majority of new content added to TF2 nowadays is community-created. And despite valve only creating a small portion of the game's contents, they're still raking in the money on a 4 year old game.
Why the Community Level Makers Win
The community level makers get some CE and a cosmetic item each time one of their maps is accepted, in addition to seeing their work included in a game they play. This appeals to everyone - people who want some sort of special in-game status (the cosmetic armor), people who want something more like actual pay (the CE), and people who just like making stuff (the fact that it's in-game).
In addition, the CE serves as a reason for people to continue making stuff after their first few, and it only takes a few dedicated people to make implementing this sort of system worth it.
Why the Average Player Wins
They get more content than they would otherwise! Additionally, the community maker rewards don't confer any sort of in-game advantage, so they aren't really missing out on anything. And if they're the sort of person who's determined to play the game for free, they may eventually make some content in order to get the CE.
In summary: Minimal effort on the part of OOO, everyone wins!
They could do this for other things as well, such as equipment, but they'd probably have more success with community levels.