IMO to build the best team you need to have grit players and PK players on the bottom 6. As good as Cat and Caufield are, they aren't 4th liners.
Also, on this team I would place Mackinnon 2C, delete Barzal and put Pastrnak on RW
wdym caufield isn't a 4th liner? according to ducharme he is!
in all seriousness though, having grit and pk players on the 4th does make sense. I was thinking for 4 lines that could just rattle off goals non stop. Guess thats why im not an actual gm