One thing to remember is that if something goes wrong, whoever's in charge may end up eating a spread of anti-reputation torpedos. High reward, high
risk.
So ch'Tharvasse might get a chance to show how awesome he is... or he might end up screwing it up somehow due to insufficient aggression or excessive rule-stickling and wind up sinking his career.
It's not doing an officer a favor to give them a position like this if we're not
sure they're the right person for the job at the moment we assign it to them. That's almost the only reason I didn't vote Nash for ground forces- I think she'd perform spectacularly, but there's a very real danger of her weaknesses coming back to bite her. And if they do it could destroy her otherwise promising prospects of serving for 20-30 years as a very talented flag officer.
Uhura, potentially, has similar weaknesses to Nash... but if this is her last assignment because of something going wrong, we (probably) haven't lost as much.
...
Hm.
With Uhura being assigned to do
this, there's an opening in Starfleet Tactical. We're going to have to bump someone to serve as Sulu's next chief of staff (for that matter, we're going to have to replace
Sulu himself soon if he's our next admiral). That will in turn open up a commodore slot (or two) in Tactical, which we can give to Nash!
Seriously, I think a year or two in Tactical would be good for her. It's an area where she's an obvious, acknowledged expert, one of the most accomplished single-ship duelists in the galaxy even. So she's not being flung out into the cold the way she'd be in, oh, Shipyard Operations. But at the same time, it also forces her to learn to cope with bureaucracy, albeit under some of the most favorable possible conditions.
Plus we may get Kuznetsova/ka'Sharren crossovers again!
EDIT:
Given that she's fought Cardassian battlecruisers like 27 times courtesy of time-loop save scumming, I wonder if we get a bonus to research on anti-Cardassian tactics from her.