So I've been considering transgender issues through the lenz of cybernetics for upwards of 20 years and I think this question misses an option: the idea of vagina+. Sure she can get a regular vag, but what other options will science come up with? What about a ribbed vagina for your (and her) pleasure? What about a vibrating one? She could get an implant that supports modular genitals. It could be fully biological or mechanical or both. Hell, she could get a vagina/penis and you a penis/vagina and each penetrate the other during sex. And that doesn't even cover the software aspect. Does she want a meter to appear in her peripheral vision that shows how close she is to cumming? Some kind of slider that could dial the pleasure experience up or down depending on how much time you have? How about a readout that shows a cockometer so she can see how many miles of meat she's taken during a session and over a lifetime?