Scotty calling Kirk "Jim" throughout the film was a nice call back to the Kirk/Scott relationship in the Prime Universe.
The Ketha Province is where Martok is from in the Prime Universe. (The Ketha Lowlands). Presumably it is uninhabitable because of the premature Praxis explosion.
Quite a bit of Ent, TOS and DS9 references. Anything overt from TNG or VOY outside of the Phoenix?