So I have been listening to Complication (Still struggle) over and over to compare it on all my headphones (it is really good, don't know if Ill hit 5000 lol) and so maybe I can help a little since you seem like a kindred spirit.
I also have the ATH-M50s and I had the same thoughts pretty much on what I wanted. Clear vocals, don't care about bass etc. I don't have anything on your list except I do have the K701 which should sound the same as the Q701 I think. They are the complete opposite of the M50s, if you really don't want bass, then they are the way to go, because instead of the M50s full overwhelming bassy sound dominating everything, the 701s have none of it, but the highs seem accentuated more and the vocals sound very clear. Probably the widest soundstage of anything I have, they just feel very very open. Only thing is they are pretty delicate in my experience, like I wouldn't roll around on the bed with them or anything. On the up side they are the most comfortable just because I can't even tell I am wearing them, its the same as wearing nothing. So yeah, really want to put bass as the least emphasis and focus on the vocals mainly and then the guitars, these really work. Much clearer than the ATH-M50s, the M50s are as far from what you describe as I can think of, pretty much the opposite of what you say you want.
Sorry I ramble alot, but the 701s are great if you don't mind the bass emphasis being night and day from what you have.
What I would really recommend though is the ZMF modified Fostex T50RP. They are closed like you are used to so you won't have to get used to open headphones. When my room mate is making noise in the other room, I get distracted with all my open headphones and feel like turning up the volume and hurting my ears. Closed I don't have to worry about that.
They have a much better soundstage than the M50s, pretty good for closed. IMO vocals are heavenly on them, but I don't feel like I have to give up anything the way I do on the K701s. I have the Version 2 which has a little bit of bass emphasis but honestly it is nothing like the M50s. This is tight accurate bass, that isn't overwhelming. You could just get the V1s with like a silver rewire, though that might go over budget, not sure. The different wire really seems to make a difference in the sound. They are the most solidly built headphones I have ever seen, like these are solid. I would describe them as lively, always unconsciously bob my head when I wear them.
Way more clarity and detail than the M50s, huge difference once I am not only hearing bloated bass.
Only downside is they won't let me fly away, they are a bit heavier than most. But they are so comfortable I don't notice the weight, I recommend the pilot pad, I also listen for 3-6 hours and such and that pad really makes a difference. Honestly I think you would love these, I know I do. They might be a little over budget if you went with the master model, but free rewires this month looks like. The basic ones are 249 though if you want to stick to that number. I would say they are my favorite headphones, on par with my HD650s, preferring the ZMF mostly and the 650s are way out of budget. Sorry I can't compare to the Soundmagics but I feel like the ZMFs perform better than most things I have heard under $500.
O and in terms of trustworthy site, Zach, (the guy that makes them) is the nicest guy ever. He will bend over backwards to help you get things the way you want and make sure you are happy. I have never had such a good experience anywhere, and Zach is just an all around cool guy.
Sorry if none of that helps at all but thought I would give it a shot since I am really enjoying going through all the songs you posted with my ZMFs now. On "Extra terrestrial Biological Entities" now and wow, vocals are so intimate and real sounding, its really nice.