Vedek Kira is the development of DRGIII, whose love for DS9 is well-attested, and whose prior works for the series, most of all Cathedral...
Not "Cathedral". David R George III's installment was "Twilight" in the "Mission Gamma" four-parter.
Sorry, title wrong, but not the wonderful 1000 pages of text (or thereabouts), and shockingly good characterization of everyone involved in the run up to going into the GQ.
(I googled Cathedral now, I didn't like its GQ plot that much actually. I was confused, thought the pocket on the planet was the cathedral, not that dull retrogressive singularity)