By 2016 (2.5years away) I think several of the 2014 players will be out of contention. St. Louis, Kunitz, Sharp and Marleau will be into their late 30s or 40, and are unlikely selections. Nash seems to be slowing down, and he was not a huge part of the 2014 team anyway. The other forwards should all be in contention. On defence I suspect Bouwmeester will not be back. He was adequate in 2014, but he was clearly the worst top 6 defenceman on the team and I suspect that the emergence of other defencemen will push him off the team. Likewise I suspect Hamhuis will still be a quality defenceman, but will be replaced with a younger option. Luongo and Smith will presumably be replaced with younger options, but with a starter firmly entrenched this is pretty unimportant.
Stamkos Crosby Bergeron
Couture Tavares Giroux
Hall Toews Carter
Benn Getzlaf Perry
Duchene MacKinnon
Keith Weber
Vlasic Doughty
Pietrangelo Subban
Murray Alzner
Price
Bernier
Holtby
First line is obviously centred by Crosby. Bergeron brings proven chemistry and elite defence to the line. Stamkos brings the finishing ability that Canada 2014 was missing, and is well suited to lining up on his off side.
Second line is centred by Tavares, who should be firmly entrenched as Canada's second best offensive playmaker. Couture brings a bit of everything on the left side, most importantly defensive cover. He's a smart player that I expect to see on Canada's next top team. Giroux was almost off the roster, but I still suspect that Canada could use him as an offensive catalyst. I also like his puck winning ability, which this line should be monstrous at.
Toews is Canada's "defensive" centre for the foreseeable future. Carter should still work as an elite utility player in 2.5 years, with solid goal scoring and top contributions defensively from the wing. Hall is a bit of a projection. I like that he is a full blown winger, I like his speed and size as a complement here and I like his ability to be be the primary offensive threat on his line. I am expecting Hall's defence to improve by the time he's in his mid 20s.
Benn Getzlaf Perry worked internationally to my surprise, and it should be better on NHL ice. Easy enough.
Duchene is almost too good to be 13th forward, but I like his attitude and realistically he can slide into a wing position on any line. MacKinnon will only be 20 at the time, and should have no problems accepting the 14th forward spot. He also happens to be a pretty great player already, which helps.
Keith and Weber should still be young enough to thrive in 2016, particularly on NHL ice. Vlasic and Doughty worked very well in 2014, no need to change that. Both Pietrangelo and Subban should be even better in 2016. Pietrangelo has some history on the left side, and I expect Subban to be too good to leave sitting on the bench or in the press box. Handedness should also be less of a factor on the NHL surface. Murray projects to be Canada's best young LH defenceman, so he gets the seventh spot. Alzner is a nice, reliable defenceman who could fit on any pairing.
Price is the default starter. Bernier has shown signs of elite play so far, and Canada's depth is not tremendous at this position. Holtby is a complete guess.
Overall, forwards are completely elite and present a lot of different options. If Canada wants more natural wingers they could select Eberle, Skinner, Neal or Kane. O'Reilly would be a great selection if they want a more defensive approach. Seguin was very difficult to leave off. He should be an absolute monster in 2016, but the forward group is loaded. I like MacKinnon much more in a 14th forward role though.
Defence and goaltending are weak for Canada, relative to the forwards. Ideally another elite defenceman will emerge for Canada, and hopefully a nice crop of goaltenders will emerge. Canada proved in 2014 that if the team is strong enough the goaltender is irrelevant (not to say Price was not very good) but that type of display cannot be expected every tournament.