Yay - Schlumpfi, denyo and me finally made it! After 4 hours of learning the map by heart we did it and even beat chrism and his crew by 9 turns. If you are interested in how to beat it just ask and I'll PM you - but let me tell you this: the most fun is to accomplish it on your own (respectively with your team).
I even drew a map where I marked the location of most enemy units. This is avaialbe upon request, too.

The mission is quite well balanced I think. You have to take a long time to figure out what to do and where to go first and I'm quite sure chrism and his crew used a totally different strategy the we did.
Just one spoiler: Base rush is pretty much suicide. We tried it a few times and resigned to "the common way" pretty soon. Have fun!