As for gamemodes i think it would be nice if treasure hunt/race is hosted (they can be both played in treasure hunt mode). These are gamemodes that where there from the beginning but where always underrated. However i don't think this solves the lack of level problem so unless enough people are motivated for this, it probably doesn't work out.

I think stijns idea is nice. Also instead of hosting levels this year, the bash could be changed to a big bash where the most important levels from the past 15 years are being hosted.