[Map]Sephene

Terran Perspective:
Walling:

-I tried to make it less awkward, but the ice tile does not allow any other formation where its just 1 supply + rax, which I find the best on 1v1 maps in tvp. It does stop the zeals, but in the event of a proxy where each second matters, a rine has to run up through from the rax below and a zeal can easily just camp outside its spawn point and trap it. Perhaps not walling at all would be the best option.
-On the subject of TvP, terran can easy fe into the nat below due to its tight nature, however, he has to decide between getting the safer mineral only below or the 3rd gas on the other side. Going for the vertical progression would make for a very passive game, but taking the dangerous 3rd gas early on makes for some aggressive scenarios, and perhaps even a slow progression through the center would perhaps make a timing push even stronger with 3 gas pumping and the center in control. Up to the terran's style to manuever.

TvZ would be pretty standard although there is the danger of mutas being a total bitch to handle in the nat. However once that's been taken care of, hunting the 3rd gas down would provide some intensive micro moments depending on the location of the hatch. There is an abusable spot for the lower expoes, making for some proficient scatters and a zerg taking the closest 3rd gas would be near suicidal anyways.
-Mech may be possible ala Flash's Katrina build, fe-->nat-->another fast cc for the 3rd gas-->camp with lith/tank to 1-1/2-2. So I'm hoping it would make for some unique games there.

Zerg Perspective
I personally think ZvP would be pretty fun on this map, although there may be some problems early game with +1 zeal rushes, due to the distance between the nat and other bases. However once they've been stabilized, they can make for some brutal July vs Rock scenarios. However if they lose that momentum, many zergs tend to use sunk/spore/lurker and play defensively, harassing with lings until they attain hive tech. Camping would be difficult on this map, so mild-severe macro deficits may be difficult for zergs to recover from.
-in ZvT, mech may be a hassle, a careless zerg could end up with a factory landing in his main or even a proxy fact + m+m push into the main.
-Probably the favorite 3rd gas expo spot would be the lower left/right corners because they are tight enough for two lurkers to hold. A zerg could probably deviate for a fourth by taking the closer gas up on the higher cliff closer to the nat once that gets rolling, it may seem too difficult to hold for a 3rd early on because they are so close to the edge and can get raped easily by a tank/m+m push.
-The closed spots around the nat are a big concern for me, I'm afraid the zerg might get clumped up in the event a forgg-esque timing attack, however he may be able to circle around that main army coming towards him and hit him from his own nat or the long way behind.

protoss perspective
PvZ: standard shit, although I think Sair/reaver would be weak,distance between the island is too far to camp and wide. Although the long distances may make aggressive play difficult, 3rd gas will almost always be the cliffed closer one.
Pvt:Formulaic and easy, shouldn't be a problem, unless toss is passive and lets the terran take up those center expoes.
mmmmm pylon walls here and there, shit's fine.

Don't think I need to discuss mirrors