Alright, so the main problem I have is with the climax.
I found it completely implausible that Lolani alone could have blown up the Lief Ericson.
Like the space Romans on 892-IV, the Orions have been handling slaves for a long time, and given that she had killed everyone aboard the Tellarite ship, Zaminon would have little motive to drop his guard.
If the episode is a whodunit, then the more plausible explanation is in fact that Kenway did it. He had motive, means, and opportunity (he left his post, remember?). Of course, getting Lolani off the Enterprise
unseen might be a problem down the line, but if anyone could pull it off, a transporter chief could. The fact that Kirk never more openly considers the possibility that Kenway beamed Lolani off and blew up the ship himself, or admits complicity, even just man to man with Kenway, is, in my opinion, a missed opportunity. In contrast, the use of the word "stowaway" in the opening act 1 log entry was smirk-worthy, because she wasn't really a stowaway at that point.
Vic's performance of Kirk is to be praised, and this has quite possibly the best instance of Kirk's signature flying kick yet seen.
I enjoyed seeing the female guard and commodore, and I love Commodore Gray's uniform (what we saw of it). The irony in females oppressing females was apropos.
I give the episode high enough marks to rank among the TOS episodes.