He'll do well but the big danger for him is clearly injuries - he moves better than he did but it'll never be a strong part of his game and obviously he's very serve reliant. He's not a serve bot like Karlovic - he's got a very good forehand for one - but if you took away his serve he'd struggle big time.
He's in the Andy Roddick mould - big serve, big forehand - pretty unbreakable when on. Roddick sustained it for a few years but couldn't stay at that level. Remains to be seen the consistency Raonic will have and how his body holds up. Think he'll be a top 10 player and can sneak a Masters on fast indoor courts like Paris (or Madrid faux-clay
) but getting a slam for the next few years with the top 4 around is a tough ask.
The kid seems nice, if rather dull so a bit boring to root for. Want to see a Raonic/Isner match just because the serving might actually be intriguing to watch. Normally find Raonic matches very difficult to watch - ace, ace, ace, unreturnable, ace - but watching the two best servers on tour against each other would have a good novelty value.
Out of the young guns I'm still sticking by Nishikori though - he has way more variety and his strokes are better than Raonic. Kei has also had bad luck with injuries but other than that he's done well in big matches - seems mentally quite strong and what's more he's a smart player to watch. He thinks on court and that's appealing.