Your character in Rack is basically a shapeshifter, but this seems to be from a gameplay point of view. That is, something necessitated by the game mechanics. But what if you actually want your character TO be a shapeshifter. I think a mechanic where you could change forms out of the shower would be super cool. Maybe you could make some alternate forms in the shower, save them, and then become them at will. Suddenly switching from fully female, to futa in the middle of the room!

Herm's looking weird with alike human penis. Wanna animal-style it!

I had some ideas for alternate types or holding units for subjects, along with some concept art

Firstly is the gyroscope/ring type, that's realy common in sci-fi themed furry bondage pics

the idea is that the subject would be in a standing pose, giving you full acess to their whole body from the front and back at all times, the 0-G varient is just to be fancy

Next is kind of more of a joke suggestion, but some people might be into it

this floor bound/head down unit is based around having full access to your subject's ass and genitals in, as the name would suggest, a face down ass up position, like the song. i imagine it'd be favored for subjects with a submissive personality and farm animals

The third is the one i like the most and put the most thought into

this test-tube/vat model uses a one-way forcefield rather than glass, giving you full access to the subject, who is suspended free-floating in a breathable liquid with soporiphic qualities that puts them in a peaceful, docile state. i imagine that you wouldn't be able to directly touch the subject with your hands or fuck them, due to animation difference, but you'd still be able to use tools and toys on them, as well as terminals or devices that give any kind of direct access to the subjects nervous system

also the lights on all of them would be colorable with an interface for aesthetics, just cus it'd be kind of cool and sci-fi, you know?

The state could have a program where prisoners could opt to be rehabilitated by the lab. they could be trained by you to be productive (or submissive) members of society, they could have a danger rating (as opposed to having to know what crime they committed) and since they are prisoners they would have to be secured at all times thus allowing for bdsm options such as leashes, cages so forth and as they would be there for potentially a long time you could track there progress as you turn them into whatever you want ( partner, pet, slave) or declare them rehabilitated and release them.

kinda like the custom made subjects in the first Rack

It would be  nice for people like me who liked the original Rack game because we didn't have to be (nice) to subjects to get them off. It would be nice to be able to customize our subjects appearance, likes, and be able to adjust their attitude and change the rate user and subject orgasms. It is a major turn off with all the new elements to appease the subject, just for a disappointing orgasm, and it will penalize you for not using their preferred sexual preference. I understand there are subjects you can do whatever with, but I like how the he original Rack played. I kinda like to be a dick to the subjects too.

You can  penetrate a slit or a sheat of another male.  Maybe a slit/slit rubbing sheat/sheat rubbing, or better, a slit/sheat rubbing, another way to stimulate the subject penis.

Things like eyepatches, customizable collars, earrings and piercings, bracelets, necklaces etc.

an option for a genital "slit" that the penis will slide out of when erect, as often seen on reptile/dragon, bird, and sea-creature characters

Can be penetrated like a vagina

it'd probably be hard to implement, but i think it'd a cool touch to add some "physics" options, where if the penis is particularly small, it can still be penetrated while erect, or if the penis is too big it won't fully retract back into the slit while flaccid

There should be a category for humiliating the subject while forcing them to cum. as its own specimen I mean, since there is going to be mind control you hypnotize them afterward to prevent any ill effects of having been essentialy broken during the session (wether they remember what happens or not)