My map is now on beta and I already published a version to Europe, but I'll love to do some testing with 5+ players. Is hard to get more than 1-2 friends to help, they are always busy with WoW, ladder or Nexus Wars :P
The reward is reputation, minerals and xp. Probably will add that info to the quest text.
I'll change the medic threat, with some heroes is pretty hard to keep them alive unless you have 2. Right now they have absolute priority from almost all enemies.
The air quest for melee units are doable usually, all units have a antiair skill at level 4, and a couple marines can kill the Mutalisk. What I wanna do for that kind of quest that the units go after you, is that fails when they kill you once, so they don't gank you on the spawning point.
Edit: when you need to test some stuff on your map be sure to call me if I'm online.