Making Picard Wesley's father has nothing to do with character development and more with a predictable clichée: of course the protagonist has to be the father of the smart kid which he initially dislikes.
Wesley could not do everything and he did not save the day week after week, only once or twice. Get your facts right.
He was a talented young man just like the new Chekov. Now whether Chekov works better dramatically is an entirely new question but you seem to be stuck on the "I don't want smart kids on starships" level.