As much as I loved (and still love) Graham as a character and seeing his back story, it is best to let him stay dead. Twice it is has been told that the dead cannot come back to life–once Rumpelstitlskin, and then Maleficent. Both stated that no spell can bring the dead back, so it seems unlikely that magic coming to Storybrooke would change anything, no matter how poweful. Plus, his death did have an effect on Emma–it did help her to rise up for the position that he once had. And it may continue to do so if or when she finds out that Regina was the one to kill him.
His role as the Huntsman is still important–I’m curious to see what role he continued to play in his service to the Queen. Season 2 will show Snow and Charming trying to take back the kingdom–will he be able to help, or hurt the two of them under orders?