Hey
Softscale, some suggestions I thought of while stoned, in no particular order or preference. No idea if any of these have been suggested before, not browsing 34 pages to find out, forgive me for any already said:
Giant wolf skin for partner, ass-to-ass-knotting, horse skin for partner, flaring animations for flared penises (really only need to be displayed during a handjob climax), a felkin skin for partner
canine/fox/horse/human/et. al. player skins -- if people are making things compatible with your character importer, ask some of them if they might be willing to lend these characters to the game (or, conversely, use that as a patreon reward -- "get your character in the game for $").
milking machine in the barn, and positions related to such. Whether player-usable or only partner-usable. A town square scene with a player-usable stockade.
More detailed player genitals.
The option to "pause" what your partner is doing, even if they're set to be "active". Something like a "Don't stop! Keep doing that!" command.
Sliders for asshole/labia puffiness. (I can't believe that's a sentence I've ever typed out.)
"Aggressive" AI -- where your partner will force you into sex (and the option to configure behind the scenes which types they will force you into). Partner libido slider, where they can be anything from unwilling to just dull to hypersexual maniacs with zero refractory period and everything in-between.
Apologies again if any of these are me either asking the impossible, bringing up something already denied, or whathaveye.
edit: yep I'm stoned and reading that at least a couple of these have already been denied, oh well.