Across 6 seasons in the NBA (across ages 19 - 24) Kyrie has:
* Averaged < 20 PPG only twice
* Averaged < 5 APG only once
* Averaged > 3 TO only twice
* Shot <45% FG only twice
* Shot <39% 3PT only twice
* Shot < 86% FT only once
He is not the most efficient scorer on earth (0.28 PTS / FGA last year), but I'll take those numbers from my 25 year old PG any day.
Also, while it's true that his defence is poor, he's only 25 - he is not a finished product yet. And I do think that is relevant because he has spent most of his career playing for crappy Cleveland teams, and has spent his ENTIRE career playing for crappy coaches - he hasn't really had good tutelage. And when it comes to defensive effort, Lebron and K-Love don't exactly set amazing examples.
Not saying I expect him to become a great defender, he's got good size and strength for a PG, so he might be able to develop into at least an average or near-average one. Probably won't, but it's possible.
Hes not the most efficient scorer on earth but his shooting splits are basically identical to Thomas.
IT just got to the line more. Kyrie has better fg% and 3p% and the playoff disparity is huge.
No question about the playoff disparity.
The problem with Thomas is that while he IS an incredibly gifted scorer, he really needs to be in a very special situation in order to thrive. He's a solid shooter but not an elite one, and due to his obvious lack of size he can't just shoot over guys - he needs space. So he is at his best when he has two or three dangerous shooters on the perimeter forcing the defence to space the floor so that he can then find paths to the basket. Once he has a line to the basket he can get a defender on their heels, and from there he can pull a variety of moves to get his man off balance, allowing him to create enough space to get his shot off.
If you watch the playoffs from the last two seasons, you'll start to see a consistent pattern there. When Boston didn't have shooters making shots, Thomas struggled. It happened in 15/16 against Atlanta, when Bradley was out with an injury and Crowder was playing hurt and couldn't make shots - the lack of threat from outside allowed the Hawks to double and triple Thomas all night - he couldn't get anything going, and the outside shooters kept bricking open threes, so the Hawks had no reason to change tactics.
Similar thing happened this year. On days when Bradley and Crowder shot well, Thomas was killing it and the Celtics were deadly. In games where Bradley and Crowder struggled to make their jumpers, Thomas faced more defensive attention, he struggled to get going, and the team was generally getting blown out.
This is where something intangible, like size, can be a game changer. Most guards in the NBA are 6'1 - 6'2, so when you are nearly 6'4" like Kyrie you can just shoot over those guys. Even he's playing bigger guards who are around his height (like Curry / Wall), his height means he doesn't need to in the air as much to get his shot off, and so he can get his shot of quicker - this means he doesn't need quite as much space from his defender as somebody like Thomas does. Combine that with the fact that he is just generally a superior shooter (near 40% for his career from three) and you have a constant threat on the perimeter - so if he catches the ball without a body on him, the defence has no choice but to close out hard. When they do he can use his elite ball handling (he is one of the best ball handlers in the NBA, period) to get straight past them for an open look.
So Kyrie's ability to go one-on-one like that means that he doesn't really depend quite so much on who you put around him. He's going to be effective, and he's going to get his points, no matter what. He is a pretty elite isolation scorer, and while team offense wins games in the regular season, the truth (that people hate to admit) come playoff time it's usually the elite isolation scorers (Kyrie, Durant, MJ, Pierce, Kobe, etc) who are winning you games with last second heroics. When you don't have anything going for you, the planned play breaks down, the clock is winding down, and you just desperately need SOMETHING - that's when those elite ISO guys are going to step up and win the game.