Niko and Wade probably would be similar to their own parents, with Niko being more open from the start to their own decisions/changes in their lives.

Rayze is the big one; if Rayze had kids he'd AGONIZE over it because like hell he'd become anything like his mother or father, for different reasons. He'd try to be there for them like his parents weren't; issue is that Rayze doesn't have a good grasp of what that means. So he'd fumble/trip and fall a lot on raising kids because he frankly has no basis of affection/sympathy that someone raised normally would. He could treat them like his Pokemon treated him, he guesses, but that isn't the same as raising a kid.