The ability to add Parametric EQ to a headphone mix in the Universal Control for my 1810c would be really nice.
I switch back and forth between my monitors and my Sennheiser HD650 cans often while mixing, and I currently use Rogue Amoeba SoundSource software to add corrective EQ to my 650s (Oratory1990's Harmon curve settings), but it's a pain to remember to switch that on and off when I'm switching between monitors and headphones. I know the UC software for the higher end interfaces has EQ, and it would be a real nice feature to add to UC for the Studio Series.