I don't think he "needs" McCoy, Spock, Scotty, Uhura or any of TOS ensemble to "be" Kirk. The fundamental personality is Kirk. The actions and decisions Kirk makes are ensemble influenced. It is in the fundamental personality that Wesley is lacking. Bottom line, there were probably better casting choices.And I'd say he needs McCoy, as well. Having a "miracle worker" in engineering helps, too.
Also, a lot of people are saying that there no need to have part of Shatner-Kirk's phrasing style. in a approach to the dialogue. While I agree an actor should never try to imitate another actor, you do have to recognize what aspects of that character help define that character and be a bit influenced by that. I go back to Pine, for example. Pine-Kirk never imitated Shatner-kirk, but there were a few times where he gave a "nod" to him. Just look at couple of his bridge entrances. They have Shatner written all over them - and in a good way. At the end of the day, I think the approach to playing great/legendary characters should be building on all those things the other actors that came before you did to helped define that character's greatness. Branaugh's Hamlet built on Olivier's Hamlet, which built on Gielgud's Hamlet, which built on (arguably) John Barrymore's. All of these actors had their own unique take on the role, but always Hamlet and the great performances that had come before.