Budget is somewhere in the range of the WA-7 or less. Less is better, clearly. I'm probably going to sell my Schiit Lyr and Bifrost as part of this whole shake-up so if there was any way I could get something that was as much or less than what I could get for those that'd be perfect, haha.
Music listening is pretty eclectic, mostly rock but a fair bit of jazz, electronic and loads of time just spent with movie scores.
I'd prefer something neutral given I'm pretty pleased with how both headphones sound as they are. I hear the WA-7 improves the bass on the HE-500, which I don't think would be an issue.