After a slow start Connor had a very impressive finish, but his ranking was probably hurt in that he got to be the 3rd piece on Winnipeg's top line with Scheifele and Wheeler/Laine(?). Not to take away from his point totals, but Barzal, Boeser, and Keller were more of the driving force on their lines, same with McAvoy on defense.
Anyway's yeah this one is an obvious choice for Barzal. It's unfortunate that Boeser got taken out of the race early, but even then he was slowing down while Barzal kept it up right through the season. Like I may not be entirely accurate on this, but I think Boeser had roughly 20 goals through his first 30 games, then 10 goals through the next 30, or something like that.
Actually doing a quick search espn gives a game by game breakthrough per player:
Oct 2-7-9
Nov 11-5-16
Dec 8-5-13
Jan 3-3-6
Feb 5-5-10
Mar 0-1-1 (2 games)
Looking at Barzal he was pretty consistent start to finish, Boeser was neck and neck through 2017 but Barzal started pushing ahead in January.