List of changes:

-Teleporters were added on the infantry routes towards the water that bring you to a Gemini feel and way to counter the top of the structure.
-The entire structure has been optimized for performance. The top spire was replaced with a forerunner spire, as was the top mid, and there are some forerunner pillars in the bottom mid now.
-The back hallways were rebuilt to put in some nostalgic tunnels and an area that feels more complete and interesting. Also optimized for less pieces.
-The lights around the structure were replaced with longer lights to use less.
-The Wraith at Red Base was moved so it is in the same view as blue side from atop the structure.
-The Red infantry route was moved in to be the same size as the other side.
-Most of the map's lighting has been redone for many reasons (thanks WyvernZu).
-The front of the bases were somewhat rebuilt for a more interesting design.
-The Gravity Hammer room has better lighting and the holder of the Gravity Hammer was rebuilt to further the original design and to allow players to pass through more easily.
-Camo was moved under the Banshee.
-The Sentinel Beam was added in the middle of the first tier.
-The Scatter Shot was move to the middle of the second tier.
-2 Splinter Grenades were moved up to the top tier.
-The filter was changed to make the ice look less green and more white.
-It is now snowing on Ancestor, scripting was added to not be snowing when you go inside areas that it should not snow.
-The large tunnels underneath were rebuilt as larger frames for less object density on the main structure.
-A lot of larger rocks and pieces were replaced with smaller pieces in their place to push performance.
-A few minor detail pieces were removed for performance gain/less object density.
-Man Cannons no longer shoot you to the middle of the second tier, they now will shoot you to the side of the 2nd tier to avoid forced engagements and to feel more like the flood jumping onto the structure.
-The bottom of the bridge was rebuilt for performance gain/less object density.
-A few other tweaks were made (minor details) for performance, aesthetic, and game play purposes.