Cool map, Dennis! I have Starcraft II just because I wanted to appreciate it at a slow pace, single player, on easy difficulty because I'm terrible at RTS games. It looks like there's lots of room for different kind of strategy and challenges though. I'd be very worried defending so many openings, haha, but like I said - terrible at RTS games. I get too wrapped up in upkeep of things and stress out too easily . On US-Servers, though, so no luck to give it a whirl, sorry!
I'm not very good at multi-player either, still stuck in bronze ladder.
Meanwhile,
I've worked on that map some more, made a few quite radical changes to accommodate for a major point of critique, which was the chokey-ness and yeah, like you, most players were concerned about the defense possibilities. The map is available on two more server regions now(America being one of them), published on those by Akinokaze under the name 'Oceanic Mountain'.
append March 6th:
A little banner I created for the map release (Paint Shop Pro 8 ):