Can vouch that the Ares II is tasty. Also pairs fairly well with sundaras / hexv2 imo.
Haven’t heard the rest of the recs.
If you’re going with the schiit stack it might behoove you to hold off on the cans and upgrade amp/dac first if you’re really looking to just increase or slightly modify the sound quality of the sundaras. Can confirm the cans respond really well to better source gear. I’d only go for new cans if you want a bit more of a drastic change (like the cans are fully not living up to what you want.