4 extra vector engines on the first stage
second stage uses 5 vectors instead of skiffs as it needs to make orbit quickly
Lunar module has only one stage instead of two to get the whole thing back
service module is now a spaceplane capable of verticle landings, instead of a boring command pod
no Launch escape tower (safety is for cowards)
No mods required, other than the Making History expansion
Here is a video of the craft flying: https://www.youtube.com/watch?v=MIy8cMku39Q&feature=youtu.be
Why not a launch escape tower?! What if something were to go wrong, and the astronauts die?