Originally Posted by merwy
But I just don't see much room for improvement. I feel like.. this is it, you know? This is all we're going to see from him. He isn't going to suddenly change his technique and play like Federer or Djokovic, he will keep his clumsy technique and good serve. What is he going to improve? Serve harder? His movement might be improvable, but he will always keep moving uncomfortably because of his length. Same with Isner and Karlovic.
He always gets lumped in with Karlovic and Isner in discussions about awkward movement, but he's really only in that group because of the quality of his serve. Physically, it's more appropriate to group him with players like Del Potro and Berdych. Unlikely Raonic's ground game will ever improve to the level of Berdych, mush less Del Potro, but it doesn't necessarily have to. Raonic has a bigger serve than either of them, and a willingness to go to the net.
In terms of areas for improvement, he could use a marginal bump in movement and endurance (those will come if he puts continues to put in the work like it seems he is doing already) but after that it's all between the ears. The top players always say that at a certain point in the rankings after which they all have significant abilities, it's a mental game more than anything else, especially on the key points. Raonic demonstrates many positive mental qualities already. Far beyond the other players in his generation, which is why he's already compiling a good record and the others mostly are not.
Who is to say whether Raonic can continue developing the mental side? If he can, he'll come across some big opportunities in his career. If he doesn't then you are probably correct his big results will be more spotty.