Biggest problem is schedules. GAF is the only community that I'm active enough in to want to team with, but I'd have to put in a good amount of effort be on often enough for practices. And then we'd need practice partners. I figure we take small steps first and do some small community vs. community events once a month. I'm sure we could get GG and some other places interested. I'm friends people in Couch Athletics, and they do weekly 'srs bsns' stuff all the time.
As for the detonator buff, Star explained in a video (although I really should fact-check this) that the detonator buff wasn't really a buff to the detonator. They lowered the Pyro's weight so essentially all explosions will send him further than before.
http://www.youtube.com/user/TwigZero
He's the one that got posted earlier. Subscribe to him, and you will learn about a lot of jump spots. The only reason I don't use half of them is because jumping into a flank area on GAF with less than 150 health and no long range artillery means death, even if my reflects are perfect.
Oh, and I enjoy Fastlane enough to have a 24/7 Fastlane server in my favorites. Prolane is just an awful map full of holes made for Scout lovers and people that need to get lost in order to avoid fights.