Meh, I think the need to "get bigger for the playoffs" is a convenient fall back, but I don't think it's that accurate here.
We lacked finish, especially from our high end talent, including Nico and Meier, and those guys don't suffer from smallness. Both guys got plenty of shots off.
As an extension of that, our PP was lousy, scored 6 allowed 2. And one of those goals for was a 6 on 4 late game goal.
And our D just couldn't handle the pressure Carolina applied on the forecheck. Bahl, our biggest D-man, really struggled in this regard, while Luke came in and moved the puck much better(though he did have a couple mistakes).
Now a guy like Tatar likely played himself off the team with his playoffs, and maybe we do use that slot to add some size, and I do think a net front PP presence would be helpful(though I could see Mercer filling that role), but in general, I think the issue was lack of execution, more then a lack of size.
Some stronger goalie play, from Vitek specifically, would have been helpful as well.