I like how there has been a leap in the gender norms. Picard really was a step up from Kirk's manly man persona, but almost a step too far. He's got some manly sides, like how he'll try to protect people, but he also doesn't fight for his people as much as he should and can be too ignorant for his own good. For example with the Tamarians Picard refuses the knife he was offered. While in the end it turned out to be a good thing that he stayed peaceful I think it's pretty unrealistic that such a passive way of approaching situations would always turn out ok. While Kirk's super assertive way might not have been the best approach either he would have died fighting for his ship instead of running like Picard did with the Borg. (Side note on the gender norms: with the girls they haven't really gotten any better as the majority of the girl's we have seen are either in low cut shirts or shown to be annoying which is really annoying in and of itself).
I think the best and most obvious replacement of Kirk was Riker I mean he's basically Kirk with a much cooler way of sitting.

He's huge with the ladies and is the epitome on manliness, just like Kirk. The only difference is that he's not captain yet. I actually really like this aspect of it because it gives Riker something to strive towards, but also adds depth to his character (how he won't leave his ship even if it meant becoming a captain) that we never really got to see in Kirk.
My bigger problem comes with Chekhov. There doesn't even appear to be an attempt at a replacement with him. The only way I can reason with this is by saying that there is no replacement of Chekhov, that he's simply too good to recreate and it wouldn't even be worth trying. I mean how can you replace how perfect he is.

And while I totally agree with my reasoning something tells me it wasn't the same as the producers, so it leads me to wonder why they didn't even try to make a new Chekhov.