Starbow mapmaking contest. - Page 3

(1) Main+Natural Base Area:
Fairly Standard Setup. Potential Siege/Blink play through the big cliff into the main.
There is a second smaller ramp leading from the natural into Area (5) of the topside for runarounds into the natural, sieges from the back into the natural or Area (2) or plainly a faster/safer connection to said Area (5) should you want to take the remote bases there.

(2) Option Half Base:
This is a slightly closer/safer third base than (3). Probably most interesting for a fast 3-4 hatching Zerg or a Protoss taking on Mech without too much exposure. The big downside of this base is that its 7mineral patches run dry very fast, each only containing 500minerals.
Beware, the highgrounds in the back are dropable!

(3) Regular third Base:
This base is a little down the road and not overly protected through walls. Yet not extraordinarily far away from your first 2bases.

(4) The Frozen Forge:
This highground area marks the central part of the map. Controlling the highground gives you both, a combat and a maneuvering advantage - while a more mobile opponent may still be able to abuse a high concentration of forces there by taking the ways around.
On either side, the Frozen Forge Area is limited by open spaces, requiring a commital to push into areas (2) or (3), while the ramp positions may allow for a soft contain onto these bases.
In some cases, you may want to expand to the close base on this area, after having acquired your third, since the distance is not too far and since it covers the fastest path into your third.

(5) Ursadon Land
The obvious part first: Beware of the Ursadon! (just kidding, he/she is nice so please be nice to him/her)
After your third, these are the bases that are furthest away from your opponent and hardest to push by slower armies. But they are also quite far away from your main production!
A couple of ramps and highgrounds can quickly give one side a distinct advantage in those areas, upon reaching them first.
Also a possible location to hide early Stargate/Starport production, since the way into the main mineral line is not that longt, yet the location very unlikely to be scouted.