Well I'm definitely in favour of Erika rejoining Starfleet! Like I said, I'd only want to base it loosely on Destiny - the trilogy comes with a lot of assumed backstory from the various relaunch novels, so you'd need to change things to make them explainable in a shorter space of time. I'm not even sure about Ezri as Captain of the Aventine, as much as I love it in the novels, it might be too much of a jump for the TV! Having her and Erika get together though... Why not? ;)
If it was set with the timeline you gave… I think that Ezri would have had ample time to get to where she was in for a captaincy. Viewers know that things don’t stay the same and a basic 22/23 year gap from the TV show would make sense.
While (obviously) I hardcore ship Jon and Erika, my guilty pleasure ship is Ezri/Erika, in the Destiny series anyway, because of Erika’s age by that point and Dax’s age… I think the two would just work and the way the Destiny books are written… yeah would be rude not too.
Destiny is my favourite trilogy, despite my absolute and utter annoyance at them writing out Erika. I actually almost broke my phone when I first bought “Beneath the Raptors Wing” on my kindle. I got so angry at some things in that book I almost threw my phone at a wall. THAT is why I’ve written my own Romulan War series to compensate.