Recommendations for next headphone

I currently have the Focal Utopias, Abyss 1266 Phi TC, Focal Stellias, and Hifiman Susvara. I have a number of amps and DAPS, the AK SP2000, Ifi audio, Focal Arche, Benchark DAC3 HGC, Woo Audio WA11, WA33. Also using Naim ND5XS2, Auralic G2.1, and PS Audio Directstream w/bridge DACs. Not looking at electrostatic at this time, until ready to plunge for a top of the line amp for that. Not considering Raal. I do like detail, clarity, and the more bass the better, but detailed bass, not muddy. Dosnt have to be super fast, I have that and more covered with what I have now, but I do enjoy different types of sound, one kind is never enough to satisfy. Meze Empyrean? Sony MDR Z1R? HD800S? HEDD ? Others?
Ag insider logo xs@2xspeedbump6
Don’t take this personally, but I hate you. 
I have no clue what my Meze Empyrean driver type is but it sounds amazing with both my Benchmark HPA4 and Bryston BHA-1. I listen for many hours each night and now afternoons too (no 2 channel amp any more). I used to get fatigue and hated headphones about 10 years ago. I took a chance on the Meze and have been shocked at how amazing it is.

I am using the WyWire XLR over the stock cable, this gets the extra little bit detail that the stock cable did not get.

BTW - I am surprised you have not picked up the HPA4, given your stable of amps. I owned the DAC3 HGC at one time and the HPA4 is much better. Though I never had headphones to compare with the HGC, I am comparing the preamp section. I used the same components on the HGC as I am now using on the HPA4.

I bought the DAC3 to use as a dac mostly in a two channel system, but now am using the Naim and auralic streamer dacs. Also added the meze and hedds to the stable last night, so now to see what else to try. 
I'd throw the LCD4 in the mix if bass is your thing.  The Sony MDR-Z1R are very close in performance to the LCD4 and can be had for a lot less.
Last night I had a problem with my work. So I started some work at 9PM and finished at 5AM this morning. All that time I was listening to the Meze Empy with WyWire Platinum XLR. I was streaming the "1976! Songs of the Year" playlist on Tidal. It was so enjoyable that after I finished my work I stayed up a little longer listening to a few more cuts. This was with the HPA4 and DAC3B.

I love this headphone system.

I like Quads with Lavricables.
I didn’t even know quad made headphones, just looked them up
Your stable of headphones and front end gear is impressive.  But I can't understand your reluctance to add an electrostatic to the mix.  Stax set the bar for electrostatic headphones and still make them.  Your budget certainly can afford you one of their best.  There are others, like Sonoma.  I'm not making a specific recommendation, as I don't have enough recent experience to do so, but ruling out an entire leading technology in a field you are so committed to, well...makes no sense to me.  
Then I need to add another 8k amp for the one headphone, I know there are others, but if I do it, i will do it properly. Not that I will never add one, it’s just that I can use my current amps with a lot more than I can with an electrostatic. Eventually I plan on the stax flagship. 
Crusty, I’ve added probably 8 or more headphones to the mix, but you might be happy to know I’ve just now added two static’s to the mix the last two days. Warwick Sonoma one and Stax sr009s as I bought the woo audio 3ES amp to use with them. I may next consider the Shangri La Jrs, and Voce next. 
How many heads do you have?
I’m gonna be sick. 
So, then I really shouldn’t mention that I was considering the shangri la sr, minus its amp and use the woo audio amp? 
If you like the sound of music....take a listen to the Grado.   Not nearly as expensive as the big guys, but (to me) more musically engaging.
@speedbump6 How does the Empy rate in your stable of phones? I am thinking of getting a second headphone. So far the Susvara has been recommended to me by the person would recommended the Empy. Love the Empy so I am assuming the Susvara is also great.
I assume you mean the meze empyrean? They are a more relaxed headphone. So far my favorite is the abyss 1266 phi tc. Havnt has time to try the woo audio wa33 with any of them yet, so, that could change as I’ve been listening with woo audio wa11, ibasso 220max and ak sp2000 portables so far. Just now ordered the Shangri la jr, so have three 

Yes, I was referring to the Meze Empyrean. The Abyss Phi TC was another I was looking at but I am under the impression that it is a bit finicky with placement on the head. I move my head around a lot to view 6 office computer monitors and I wanted something that stays in place. The Empy does stay in place. I will have to demo the Abyss instead of buying blind like I did with the Empy.

I have the Benchmark HPA4. I wanted to get a second amp and right now have narrowed it down to a second HPA4 or the Headamp GS-X mini. I will do a bit of research on all the amps you have.
I would also consider ZMF Verite. 
Lol, well that is one of my recent additions. Waiting on it to be built now. 
The abyss is looser for sure, but don’t think the movement is a problem unless you bend down a lot. The sound it produces I think is much better than the empyrian. 
Interesting feedback on the Abyss. Very curious on that now.

Another amp I want to check out is the new T+A HA 200. T+A make some impressive DACs and this unit has a built in DAC.
The reviews on the that amp seemed to be very good.