Finally came up with a travel/vacation plan for the summer which I am more sure than not is the one I'm going to stick with. I decided it was best not to combine MDF with my European trip since many of the things I want to do in Europe are in late June and July and I figure asking for a 2 month long vacation from my internship is like asking to be fired.
May 27-31: MDF
June 24 - July 18: Europe
* June 25-26: Paris, FRA (Magma concert)
* June 27-30: Dusseldorf or Berlin, GER
* July 1-4: Zurich, SWI (Zurifascht festival)
* July 5-9: Geneva, SWI & Lyon, FRA (possible ZZ Top / Jeff Beck concert)
* July 10-12: Vienna, AUS or Munich, GER
* July 13-17: Prague, CZE (Onder and Obscene Extreme festival)
I believe this to be a recipe for epic win. And, based on my research, the combined total for air and rail fare on the Europe trip (not including whatever metros I use for intra-city travel) should only be around $1600.