Charge players per level submitted, and have various game masters run through them during downtime to test them out. Heck, we could have "community testers" chosen from the community each week or so to test levels submitted by others. Highest rated levels go through to the game masters to try out and verify the integrity of the level.
Would we choose existing pallets? Yes., It would be neat to have it based on a tile grid! We could have various assets from levels (unique ones too. Those fiendish portal ground thingies in MotT could be neat to play with) to customize with. Also, if we don't customize our own connections, do we simply connect them to our own needs? Do we just place spawns for things? How is height determined?
SK already has premade rooms (in clockworks floors) that can be traversed in both directions (remember the supposedly useless button outside locked gates?). Allowing players to piece these together would be the first step in community made maps. Next you could let them work with creating mazes in a wide open map (similar to the low gardens).
For fairness player would only be alloted a certain number of monsters, with trojans and deadnaughts being very costly and minis very cheap. Rare monsters would not show up at all so gun puppy, oiler, cube, kat farms would never have whatever rare monster spawn over them. Bosses would not be in because many have special requirements to beat or gimmicks they use in battle (bell, royal polyps, lazers/walls, water, etc).
There could also be a mode that lets players populate levels with different monsters, just imagine FSC rooms where slags used to spawn now has Lichens!
What do you think?
Credit to: Fangel and Holy-Nightmare.