I have been musing about Strange New Worlds with my brother this afternoon. Some of this is me and some is him.
I am frustrated a bit by how hard they leaned on legacy and legacy-connected characters in the cast and I've talked about that before, but where a legacy character really belongs is on the list of cadets that Pike will save. Chekhov would be too on-the-nose (and that probably makes him likely...), but Saavik would really hit the spot, I think, unless she is too young. Someone that mattered, but please not a main character. And I think Riker's grandpa would be corny too.
I read a while back that the producers told Rebecca Romijn that they wouldn't be sticking her in a miniskirt and she told them to do it, but change what it means. They have a few different girl uniforms and that way it isn't what Starfleet sticks girls in. It is just one of their options. And it might make a funny explanation for why Kirk's crew a few years later is so male. He may have a strict no-pants policy and a bad reputation that keeps girls from signing on under his command.