I wrote four Gallifrey fics for Yuletide, one of them novella-length, and thought this might be Relevant To Your Interests. One is a stand-alone...
Presidency2,000 words, Romana/Brax, PG
The prospect of ruling Gallifrey is enough to daunt even the most confident of Time Ladies-but with a little help, Romana thinks she may just get used to it.
...and the others form a series...
The
Time and Again series (which ought to be read in order)
Five Times Romanadvoratrelundar Missed the Signs, and One Time She Couldn't Possibly Ignore Them6,500 words, Romana/Fourth Doctor, Romana/Darkel, Romana/Brax, Romana/Pandora, Romana/Narvin, and Romana/Leela, PG
The most powerful woman in the known universe has a tendency to attract admirers. She would probably find this a distinct annoyance-if she could ever be bothered to notice.
Another Time4,000 words, Romana/Narvin, soft R for not-too-explicit sex
Wherein everyone takes a break from threatening Narvin to save the universe-or possibly the other way around-and it is conclusively proven that Romana's childhood nickname was absurdly ill-chosen.
A Time For Every Purpose28,000 words in three chapters, Romana/Narvin and a bit of Leela/Andred, hard R for sex
Romana knows that relationships are always complicated-but being the President of Gallifrey, she thinks, gives her a far better appreciation of that fact than most people can ever imagine.
Also available, for them as prefer it, on AO3,
here.