I own both the ATH-AWAS and the R70x. Unfortunately, I haven't heard any of the headphones you own other than the HD650 but it's been a number of years since I've owned or heard one so I can't give you a meaningful comparison.
Like you, I stepped away from headphones for awhile but with working from home because of Covid it seemed like a good time to build a system again. Over the years I've owned a number of the Audio Technica woodies. They've all had beautiful midrange characteristics but also could have some odd coloration that inevitably bugged me enough that I sold them. I was really drawn to
@Malevolent and
@Nostoi's descriptions of the AWAS though, so when one came up at a reasonable used price I snagged them. That has turned out to be the best audio purchase I think I've made.
The AWAS has that beautiful midrange that the AT woodies are known for but it manages to do this without ending up with any honky or nasally coloration. Vocals are just stunning, acoustic guitar sounds rich and inviting without being too overdone. It's a smooth headphone that still manages to have fairly tight, punchy bass with decent overall transient speed and musical pace.
I've always been sensitive to exaggerated sibilance so I've leaned towards darker gear in an effort to thwart it. In my setup, the AWAS manages to have more treble presence than I've typically had in previous setups and it does this without a hint of added emphasis in the sibilance region. It's been a refreshing change to have such a sweet treble region.
For awhile I struggled with the bass though. I wanted eke out a little more weight than I was getting in the setups I had at the time which led to a bit of experimentation. Oddly, the missing piece of the puzzle seemed to be a proper S/PDIF cable. When I replaced the Monoprice cable I picked up off Amazon when I bought the BlueSound Node 2 with an Audio Sensibility Statement cable, I was floored by what it did to the bass. I really wasn't expecting any real difference, I just wanted a cable that was decently built and would stay connected to the Node and Ares II. It's still no bass monster but now it feels like the bass is properly balanced with the rest of the spectrum.
It took some time for me to conclude that the AWAS is pretty much my endgame. I've tried a number of other decent headphones like the Aeolus, D7200 and Liric among others and the AWAS always comes out ahead. It's really a shame that it hasn't seemed to receive the attention it deserves. I tend to wonder if some of that comes down to system synergy. I really liked the AWAS when I first got it, but since making upgrades specifically to try to bring the best out of it, I've really been amazed at what it's capable of. In fact, I expect I haven't yet discovered its full potential.
As for the R70x, I only recent picked up a pair out of curiosity. It's also a really nice headphone but it is not in the same league as the AWAS. It does have a little more bass presence, especially sub bass, than the AWAS but the R70x can't touch the AWAS in anything else, not even soundstage. Well, except maybe comfort. The AWAS is super comfy but the R70x can feel like your not wearing anything at all.