We'd probably have an entirely different show. Well not entirely. But the characters would need to be written differently seeing as they won't have to deal with Rose's "death" for character development. Steven I imagine would be the same for the most part except he'd have his mother. He'd still be the main character and focal point of the show though. Ummm......conflicts with Homeworld would still be a thing except we'd have better knowledge of it through Rose's past since she'd actually be around to fill Steven in on things. If things would be better if she WERE around well that's kinda hard to tell because the show we have is already pretty awesome, so I wouldn't change things personally if you asked me. But Rose being physically around is something neat to play around with. Like I said though, the story would have to be altered quite a bit for it to work so idk.