Re: Why did Dax remove her spots?
^Agree with above. I think Trills in Starfleet were something of a rarity in Starfleet or the Federation during Kirk's time. Curzon is the only one I know of for sure. Jadzia probably didn't want to arouse suspicion by showing off her spots. Same with Worf. Klingons were around, but one sitting by himself on a Federation space station would have raised too many questions. And no, I don't believe those questions would have had anything to do with his improve make-up and ridges.
"He clapped his captain—his friend—on the shoulder. Yes, this man was very much like James Kirk, in all the ways that mattered." --Christopher L. Bennett-- Star Trek: Mere Anarachy, The Darkness Drops Again