I think they will be defeated or split up long before wrestlemania but I like your idea of them going after all the titles. Personally I have no idea what is going on with the booking. They have a lot of great talent and characters (Rhodes, Ziggler, Sandow, Cesaro, Bryan just to name a few) but it seems that Punk and The Shield are the only two entities keeping them above water. Triple H/Lesnar has grown stale and the Cena/Ryback fued would only stay interesting if they keep Ryback a tweener instead of full heel. Kevin Nash put it best when he said something to the extent of the writing should be focused on character development. My belief is if they stray away from creating full heel or full face characters and actually develop the persona than it would be much easier to write interesting fueds. Much like they did in the attitude era and in the original ECW. Of course, that would probably mean little kids wouldn't know who's the good guy or bad guy. God forbid.
Ok, I'll get off my soap box now haha.