I would have made Kes more interesting and better utilized in the series. But I'd be more cautious about how "child-like" and "curious" I'd want her to be, just to avoid another Wesley debacle.
"Childlike" & "curious" wasn't Wesley's problem. He was too much of a super-genius was the problem. This is supposed to be the best crew in Starfleet yet its top minds are often getting out-thunk by a teenager.
I'd play Chakotay older & more experienced--like, most cadets mention him in the same breath with Kirk & Picard--and played by a different actor. (Who? I don't know but anyone's gotta be better than Beltran.) Then go with a younger Janeway played by Susan Gibney who was originally Voyager's XO before the captain was killed when they were 1st pulled to the DQ. Granted, Janeway & Chakotay's youth vs. experience conflict might seem a bit cliche but at least it would be conflict of SOME kind!