Seeing Archer again would be fine - or T'Pol, for that matter. I don't think it will happen.
In a Mirror Darkly had Archer attend the launch of the 1701 in 2245 and die that evening, not canon but I'd like them to stick to that, he's not someone I'd want to see in the new series.
T'pol though, sure, she'd be about 170 by then.
I can't remember how long Denobulans live, but a senile Phlox could be interesting.
