I would love to see both of these so long as Bryan walked out with the title at the end of the night. If Bryan's not going to take on HHH, then I have two ideas:
a) Bryan wins the title at EC and sets up the triple threat
b) Bryan faces Sheamus in the Mania opener and loses through interference from Kane or HHH, but returns post title match with Vince (could also be Hulk if Hulk is going to be an authority figure on Raw/Smackdown post-Mania), who awards him an immediate title match against Orton, who has just retained the title. Bryan then beats Orton to take the story full circle and also be a little bit of an homage to Hulk at Wrestlemania IX.
As for the Shield triple threat, I'd expect Reigns to win by pinning Rollins and a feud set up between Reigns and Ambrose prior to any unification feud between Reigns/Ambrose and Langston.
wk