For the actual match (since I, like others, feel they'll just Freebird this title reign afterwards anyway), I can see them going with a combination of either Ambrose/Rollins or Rollins/Reigns. With the former, it seems Ambrose and Rollins go together well and I can see Reigns being a sort of Diesel-like bodyguard on the outside, just waiting for either Kane or Bryan to be thrown to the outside so he can attack and destroy them (clothesline, slam into the steps or the ring post, etc.)
On the other hand, Rollins and Reigns counter balance each other quite nicely - Rollins can be the athletic one who uses his quickness to his and their advantage and Reigns is the powerhouse muscle who comes in with the big power moves. Team Hell No works the same way, with Kane as the big man and Bryan as the one using technical skill and quickness to his and their advantage. I can also imagine a spot in the match where Kane and Reigns want the other's partner to tag the other in so they can go at it to see who the true dominant big man is. Imagine Kane getting tagged in by Bryan and then Kane telling Rollins to tag in Reigns because he wants some of him. Meanwhile, during all of this, Ambrose can be sort of the observer on the outside since he's the closest to being the 'leader' of The Shield that there is. (Notice how virtually every time The Shield begins to speak, Ambrose always speaks first.)
The one combination I can't see happening is Ambrose/Reigns.
