Seems like a cup winning team needs two out of three of:
-High end #1 Center
-High end #1 Defenseman
-High end #1 Goaltender
If a team doesn't have all three, then the empty position needs to be filled by at least a capable individual that elevates his level of play during the playoffs. Doesn't have to be elite, but has to help put his team in a position to win and make the saves/plays that need to be made.
Pretty much every cup winning team has good depth, and players playing at, or above playoff expectations. (Ex: 4th lines and bottom pairings can't be irrelevant)
Seems like each team has their own specific personality, (super skilled, tough and intimidating, etc) but seem to have the basic makeup of what has already been posted. Never bought the idea that you needed to "wear down a team physically" or have some specific element to your game, other than having the roster requirements already listed and having a good head coach.