I was thinking that instead of booking the usual tripe for Mania with all the part timers matches and Reigns annual coronation (or coronation abortion) why not combine them all into something people actually may want to see or get invested in?
How about a Shield vs Cena, HHH and Undertaker match?
It puts the part time guys all into one match.
It's easy to book with a simple "we are sick of you guys coming back once a year and taking big spots on the card" angle.
It hides Reigns in amongst the Shield instead of throwing him out there to die again.
It allows Taker to just play a very limited role, do his signature stuff and not take the pin (although that doesn't really matter anymore).
It gives Rollins and Ambrose significant roles on the card.
It gives The Shield a worthy team to face….bearing in mind that they looked WAY above everyone on their last run.
It should be a fun and possibly even very good match.
What's not to like?
I don't think it works as a full on main event, but second from the top, why not? It's got a nice meta-textual element to it with the part-time v. new generation stuff and it should be good. It could work.