#1 Contender's Match(es)
With Wrestlemania being the stage for the largest spectacle in professional wrestling would it make sense to have more of these types of matches? Think about it. We know the WWE title, and WHC title will be defended. That's guaranteed without a question. However, we know the next night is Raw, and it's live. With stars like Orton, Sheamus, Punk, Miz, Lesnar, Daniel Bryan, and such who are obviously not all going to be involved in WHC/WWE title matches at WM what do you do? Why not more #1 contender's matches for the WHC, and WWE title?
That way if you have Cena vs Rock for the WWE title, and Del Rio vs ??? for the WHC that leaves room for solid booking for the other stars. You can set up at least two more matches that are centered around those two titles. Perhaps WM turns out to be Cena vs Rock, and Del Rio vs Orton. You can have a match with Sheamus vs Big Show, and the winner is the #1 contender for the WHC, and will sign a contract live on Raw the next night. Then you have CM Punk vs The Miz, or Jericho. The idea is that you have other key players for those titles in contention, and it's made clear through these types of matches at WM.