I think this mix is so dense that you could get away with a good deal more panning to make more space for things.
The vocals sound so dry - they kind of don't match the other elements.
I like this. Kind of has a The Pillows vibe, or maybe a calmer Shinobu song.
The only thing that really stuck out to me as that some of the leads aren't sitting quite as well as they could. The siren-like one under the vocals feels pretty buried for e.g.
They're all panned pretty mono. If you spread them out a little more, you might have more wiggle room to turn things up.