Aesthetically it is a pretty cool map, though the terrain could probably use more work. The frozen waterfall looks a bit chunky (google frozen waterfall, I guess), and doesn't seem to come from any particular source.

I can't quite understand why there are crates scattered all throughout the snow. Having them near the crashed UNSC ship makes perfect sense, but I think rocks/ice would be a better choice in the rest of the map if you want cover. The background Forerunner object adds a nice atmosphere to the map. I feel like the top structure would be a very overpowered position, as it looks like you can see the entire map from there.

The last thing is just something I personally find off-putting, so feel free to disregard. By saying that your own map is "incredible", or that it has "AMAZING detail never before seen", it just seems like you're both overselling your map and underselling the work of other Forgers. Sorry if I have caused offence.

Also, would Phaeton/s work on this map?

 

Hmm, interesting. I have no idea what the physics bar even refers to..
OK, fair enough. I hadn't downloaded the map to actually check. It just looked like a very strong position from the video.
Alright, I guess it did make me click...
Please don't misinterpret, I like the map. The Forerunner architecture is mostly excellent and the large play space is good, I think there are just a couple things that could be touched up.

 

This was tons of fun to build on. I really want to do more Forerunner things.