Hmmmm, I listen to literally everything!
For electronic and other bass heavy stuff I have my Fidelio x1. I don't see any chance that that headphone is going to be replaced by anything. The only thing I hope is that the bass is tightened up with a new DAC. (Macklemore, Shpongle, Hardstyle)
For rock and metal I am planning to get a Grado. Don't know which one yet, tough. I have had the rs2i for a week and damn it was awesome. Very sweet sound! I have also auditioned the ps500 and the gs1000. I liked the ps500's thicker sound but it wasn't as airy. The gs1000 just really, really, reaaaally sucks. It's like sticking a few needles in your ears. (Soad, Nine inch nails, Rage against the Machine)
And for other music like psychedelic rock(pink floyd), normal rock(dire straits), beatles, blues like solomon burke, Joe bonamassa or prety much everything else I still need a headphone. I think the hd558 comes very close to my ideal sound sig for all those music styles. I'm probably going to buy all the senns from hd518 and up just for the pleasure of collecting and fun whenever I get the money. But first things first and that is one that will satisfy my needs. I'm a bit scared that the 558 is too low quality but I just need to check. Maybe the hd600 is a good candidate? Perhaps the hd700?
I think I'm looking for a lovely open sound just like grado delivers but with the missing bass since every other music style needs it more. :)