It is really hard to give a reference as we all hear differently. Of your four:
1) Never heard or owned the D7200. Huge fan base though.
2) Just got my HE-R9's about two weeks ago and am just loving them. Loose and sloppy bass sound. Very fun if you're in the mood and with the right music. Isolation sucks. Wires can be problematic.
3) I love my Cascades! Bass for miles and pretty clean for a bassy 'phone. The headband, IMO, is horrible. Uncomfortable and lacking cup clamp. I prefer the XL leather pads. Will likely never sell.
4) I like my Elegia's, but do find them bass light. Probably the most well rounded sound of the four. Good bass, great mids and enough treble for lots of detail. After the HE-R9's, they felt too bass light.
I will probably move up to Celestee or Radiance eventually.