Thank you! So far I've listened to the FiiO FT5 and Moondrop Para planar headphones, which seem to be later models than the Sundara.
The FiiO had a comfortable fit and a self-adjusting suspension headband. Compared to the Moondrop which had a terrible fit. Unfortunately, both had quality issues. That's why I returned them.
I have the sundara, the dca aeon 2 noire, DT 770 Pro (250R), and sony 1000xm5 (noise cancelling for travel). So, I have an open-back, closed-back, and noise cancelling. Plus the DT770 are some utility cans for use other places than my desktop.
I find the sundara very comfortable. They have super large circular ear pads and a pretty firm strap adjust with detents, so it stays in place. The dca noire is a tighter fit around the ear, so is a bit more placement sensitive, but it's closed so that likely helps keep the noise out better. The strap adjust on the noire is a bit loose when not under pressure being on the head, so I usually need to adjust it every time I put them on. The sony are very nice too for a noise cancelling. The DT 770 are pretty comfortable too, but not the same class as the others.
I use EQ on my RME ADI-2 Pro or in SoundSource for the sundara and aeon2 noire (I'd EQ the DT770 too if I used them there). Nothing major, but it is better sounding to me.
You can't EQ fit and comfort, so find a decent pair that fits well, then you can likely EQ them to taste, assuming they are reasonable close. At least that's my approach.