I have a better idea, keep most of the week standard, so it isn't full of gimmicks...
I always hated gimmicks in servers. Most of it isn't fun, like Saturday, the levels ended in five minutes... There was no time to do anything fun except shoot at the Harvester for points and see who got the most at the end, on each level...
A better idea would be to start running fan levels full time mixed in with standard levels, so the game's longevity isn't based on five minute rushing, or sniping only...