One thing I've heard big boys like Tiesto and AvB do is add an echo-like effect along with HP filters - not necessarily during a transition but I think it could work really well in such a scenario.
http://www.youtube.com/watch?v=ULw4Ci4NBjI - skip to about 3:55, then again with a HPF at about 4:20
I know my BCD can't do such an effect and I'm not sure how to get VirtualDJ's echo effect to sound exactly like I want, but do you have any experience with this? I think it'd make for a great next video if you don't have one planned already
