Burnham's mission brief was that she'd take Discovery to her designated coordinates and then leave Zora to wait. Given the nature of the mission I wouldn't be surprised that it was a skeleton crew of Red Directive operatives, including a lone officer on the bridge, and mayhaps someone qualified in spore drive ops down in the Tank.
As for leaving Zora for an untold long period of time being mean or not, she IS an artificial intelligence. AI rights issues aside, we know that they can experience time differently than us meat popsicles... Not in Trek, but there's a ship's AI that ran a JMC mining ship alone for three million years and he barely went crazy at all, so it's surely within the realm of sci-fi writing to have Zora do this mission in a relative flash for her consciousness.
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Changing tracks a little, can we spare a thought for the 3
3rd century uniforms! They're thankfully still colorful and perhaps a bit more militaristic, which I do like; and the black of Discovery's uniform set has been banished once again. Burnham's Fleet Admiral outfit still keeps the rank pips tiny and obscured, which I'd taken as a way to de-emphasize rank over position or responsibility - her flag epaulets do add more emphasis on her four-pip Admiralty, though.
Leto's Captain uniform brings back the discrete pips and puts them in a visible location and at a size where you don't have to squint; however it's good that he's a fit man, as I daresay that humans like me who can have a bit of a chin at my age would have their ranks covered up at times. Lurians too. And finally, the tricom gets a do-over, being a big bigger and having a more distinctive look that recalls the "evergreen" Star Trek logo that was used across all corporate media for a while in the 1990s, plus stuff like the Generations movie and the
"Journey's End" TNG special. always liked that one.
And let it not be said that uniforms that look impossible to get into or out of can come back too! The earlier 32nd C uniforms had clear zipper seams even though the clasp at the top was made to look like it split down the middle when open, whereas in "reality" it was velcroed across the top. Here, none of that matters, as a tricom tap will call whole wardrobe changes more casually than before, where spacesuits seemed to be the only thing that zapped on or off (as a function perhaps of the away team gear). Quick change magicians are clearly unemployed a thousand years in the future. :P
Mark