I can't see any more new harem members added to the roster.
As for Thim and Kit, them being transformed into women, physically, wouldn't change anything. So far as we know, they're both straight. So even if they were made to have women's bodies, they'd still only be interested in women. And given how neither one of them are trans, they'd almost definitely want to find a way to get their own bodies back.
So for you to get what you want, whatever causes the transformation would have to change their gender identity and sexuality on top of their bodies, which would really dark and much darker than the norm for this game. Certainly if it was done against their will.
Yes, there's been weird body modification in the game, but with the exception of the rape fueled human milk farm, it's all been at least implied to be consensual.
Raene is the only person on the ship would could conceivably volunteer for such a transformation, but given how her current course of HRT is working nicely (in universe), and how well her being trans is being handled (in universe and out), I don't see Raene getting changed like that.