Based on your response, it sounds like the DT1770 is your natural next step up. Though, I would recommend the DT1990 (though open-backed) more because it does almost everything right with the analytical pads and packs plenty of bass. One of my favorite headphones is the Sony MDR-Z1R. That'll definitely deliver for hip-hop and EDM which are a couple of my top genres I listen to. If you're not trying to spend that much, then I would recommend the Sony MDR-Z7. I must say that they are warmer sound headphones but there is plenty of sound and detail packed into the highs. The other final option for over-ear would be the Campfire Audio Cascade headphones. I listened to them briefly at a meet, but they sounded really good.
If you're okay with on-ear headphones, the Audeze Sine sounds great as well. The 1More Triple-Driver Over-Ear headphones sound close to them and pack plenty of bass. I must note that they're really on-ear, not over-ear headphones. Hope those options help.
Great amp choices, by the way. I love my DarkVoice, and I have the 789, but have the Monoprice THX portable that sounds great.