I just pick maps that I know are playably balanced that I fancy playing. this is really just "keep youme ammused" event repackaged as map testing.
Also I tend to only do maps that have their latest version already on the server in question allthough i did upload backpier just now since I'm desperate to try it out.
There was a little bit of discussion in the chatroom too, cornfield was suggested there and chrono had just entered, reminding me of koth_chrono