To put go fuck yourself on a whole other level.

where in the lab, a subject is transformed from one species to another

Mutate a subject's tongue into a cock. Can be great when combining with kissing and sucking, as well as gathering more samples

Tentacle pit / rack / thingy:

Basically a large pool or pit that the subject is lowered into and teased, tickled, penetrated, or sucked off by tentacles. You can either choose which actions the tentacle pit does or have it do things to the subject at it's own will. There should be different types of tentacles (Sizes, lengths, textures, etc.) For ones that would suck off the subject, maybe add an x-ray of it and different inner textures as well. (maybe tentacles inside the maw)

Living clothes / biosuits

Pretty similar to the last one but more fit for orgasm denial and tickling. Imagine Zero Suit Samus but the inner layer of her bodysuit is all tentacles and sort of a fleshy texture. Moving and jiggling to tease the subject. The more the subject resists or moves around, the more active the clothes become. Added xray would work and also protruding tentacles at any openings of the suit (neck, crotch, sleeves)

Palmjobs

Post orgasm torture yaaay!

After a subject orgasms and there's jizz all over the tip of their penis, you can rub the tip with your palm and cause them to either orgasm again or squirt. 

Basically this would be used for different tentacle situations...

Somebody like in clothes play and cum under that. So, fek ,can you add this feature in R2CK?

There's already a slider to set the masculinity and an option to set the muscle build of a character, but I would like to be able to have a couple more sliders for specific muscle groups like biceps, pecs, thighs etc. For example, I am a sucker for big pecs so I would like to buff them even further than is possible now.

I think it'd be neat to give an Age stat to characters. It could affect hair/fur coloring(greying on more mature characters) and body shape(perkier breasts on younger characters, less muscle on older ones etc), Younger characters could be more likely to have less experience, age can affect sensitivity and maybe there can be a preference for certain ages.

A short band of large anal beads, 2-4 beads. at the very ends of each bulb, a portal device. Just insert one bead inside and anally fuck someone, either a constant inward motion, constant expulsion, or pistoning back and forth, the beads moving in between both portal ends inside and outside the ass. For even extra intimate fun, get two devices between two persons, and switch portal ends. Every-time beads goes inside one person, the same beads go out the other, and vice versa.