KSP takes a long time to load. Especially with mods installed. I got the impression that loading 3d models of parts is the main problem. Other games seem to load 3d data much more efficiently, so I thought I'd look into it. It seems 3d data in mods comes in .dae (COLLADA) files. That's a slow interchange format, but it's apparently converted to .mu files when KSP is run, to improve loading times later. But loading times are still quite slow. .mu is Squad's format, and they asked people not to create a .mu decompiler/converter. Why? (Well, I know why, I just don't think it's a good reason.) So the problem seems to be the .mu format and/or code. Maybe it would be faster to use BinaryFormatter: http://answers.unity3d.com/questions/64317/is-there-possible-to-save-scene-gameobject-data-on.html Even using JSON might be faster: http://whydoidoit.com/unityserializer/ Bitmaps are stored in .mbm (MultiBitMap) files. Zipping a 1.1mb .mbm file gave a 86kb file. CPUs are faster than HDs now so some simple compression seems worthwhile. This might save some bandwidth and make loading faster.