This one might actually be tricky to pull off. I mean, are you Kickstarting a comic you've already drawn? If so, going back and redrawing stuff will mean taking extra time before it's printed, which might cause your backers to complain, etc.
The higher tiers I usually see from comics-Kickstarters are a.) tiers including original art (as in, drawn on actual paper) or commissions in limited amounts, and b.) multiple book-packs. Instead of getting just one book, the backers on that tier get two, or five, or ten books.