I went from the HJE900's to the VSonic GR07 (~$150-160). I'd say it hits up 2 of your three criteria as a solid upgrade. I'm writing up a little A/B comparison but without getting too much into it, I upgraded mainly for soundstage, which makes the CZ's, while having good depth, seem almost 2D. What I got as a pleasant surprise is clarity, which I never thought about, and could not even imagine at this level just going by the Panasonics.
About your third criteria, the bass, there's more quantity with the Panasonics. The GR07's can be intense when called for, but won't shake your head as much as the CZ's which do it every chance they get. But the VSonic's can be delicate in the low end in a way I never experienced with the CZ's., Texture across the board is excellent which helps you feel the music in the GR07's, as does the good low end extension. Think of the bass of the HJE900's as a double espresso and the GR07's as a really good cappuccino.
In the end though, it's a really different sound signature. The GR07 presentation and clarity are really addictive, and being sensitive to certain higher middle frequency's at high volume levels, I don't miss that part of the HJE900's. What I do miss a bit is the raw emotion in mainly female vocals that come with the harshness at those frequencies, kind of a double edged sword for me =/. The GR07's seat you a few rows back for most vocals and are definitely not harsh while still being really crisp and clear.
As far as the music you listen to on the GR07's, I have absolutely no problems with the rock and metal I've run through them. Guitar textures are great. Male vocals are pretty solid. Presentation is generally spacious, like being at a live show. Rap and Hip Hop, I don't get the same midbass rumble on many tracks in my collection as my CZ's, but the thump is most certainly there and I can confirm that listening to some EDM which they are absolutely great for.
I think you'd be missing out if you didn't at the least read some reviews that can more technically describe their sound quality and signature.