As the header says I like the portals but it's not the most important thing and would probably be a bitch to program.

something like a electric slime/goo that we can stick to the breast, pussy penis to electrostimulate the characters

Just like RACK, have this available for use or have requested by subjects.

Half of the option is currently available in the game, this can also help keep some subjects busy if you like selecting more than one subject at a time

Just insert and work on the other subject till ready

Oftentimes a guy will rub his weewee up and down on the girl's clitoris externally before taking the plunge. Should there be the option to penetrate the vagina without having to cancel out the current action (of rubbing the clitoris with weewee)?

The ability to use ice as a toy would be nice. For lack of a less graphic way of putting it, inserting smaller pieces of ice into one's butt during sexual activity feels amazing. Being able to do that and more, such as perhaps an ice dildo or something alone those lines, would be fun.

Also, on a similar topic. Wax play might be interesting. Not my bag but it's along a similar vein.

There could be an automatic dynamic or preference between predator/ prey species similar to how the larger vs smaller partners system works. No vore, just innate aggression or submission based on species. 

Basicly, a rack that uses the wormhole/portal technology at each major joint and genitals to allow moving some of the subject's parts around

Ok, so I know Fek has the milking machine planned. What I would like out of this is an automatic mode, where it brings them to orgasm then waits for the next round. Think of it as a set and forget deal.

Just kidding, but it would be nice to have multiple sex organs.