Can anyone link me to some desired shaders? I'm looking specifically for very good looking SSAO, DoF, and Sunshafts. It seems the ones that came with MGE XE 0.9 aren't very visible.

Best to look in http://www.gamesas.com/topic/1462188-mge-xe-shaders-library-and-development/ for shaders. For what you described though, you just need to edit the tweakables in the shaders you specified. Open them up with the shader editor and the tweakables are usually somewhere at the top, they often have comments describing what they do. Good luck!