Personally Batista is a cop out of the highest order. If he is only here until august, he can't have a proper title run, and with no actual feud then it will be a slow 2 months for the title picture.
Here are my alternatives for how it should have ended;
Daniel Bryan number 30, wins the rumble. Old memories of being screwed out of his matches with Orton come back, who has the Wyatts behind him to get into the head of Bryan. It leads to the main event at WM where Bryan has been fighting the odds both mentally and physically to win the championship at the end of it, bringing an end to the year he has had.
Roman Reigns wins, triggers the break up of the sheild when after a couple of weeks tensions start to build. End result of this storyline is Randy has the Shield members behind him against Roman as well as the authority. When Roman wins the title he is put over instantly as a massive new star which will help carry him through the next year as a good enough champion, and a star is born as they say.
Punk Wins. This leads to an all out authority vs Punk storyline at WM. Predictable but ends a year long story with Punk back on top. Could start new feud after WM by him giving danel Bryan shot at title and leads to Brock/Batista challenging him in the end with the idea of pushing both Punk and Bryan in the coming months.
Sheamus wins, return of the celtic warrior puts him really over on his return, 2 rumbles in 3 years strengthens his postition in the match ove rthe coming years and faces the prospect of face vs face against Cena. Then turn Sheamus on raw so you lead up with good vs bad. Alternatively have sheamus feud with someone else and have them lift the title off cena next month, like a heel batista leading to a main event noone thought of.