Pretty sure it's all about preference. I can play just as fast on my flat-radius classical as I can on my acoustic, on my JPM, Ibanez, Schecter, Squier, etc...
That being said, the guitar has to be set up to your liking; I think that's more important and allows you to play more comfortably than specs in general (like how y'all mentioned Malmsteen uses 8's tuned down a half step).
I do not like... sweep picking. I've been dabbling in economy picking for more EJ-style phrasing, but I just can't get into the long, overdone sweep picking.