I don't see any reason to change things up. Lethal injection still seems like the most humane method of execution. Sure, on very rare occasions, it may potentially go wrong, such as with the Lockett case, but that was just an isolated incident. If given the choice between a method of execution that has a possibility of being excessively cruel if preformed incorrectly (lethal injection) versus a method that's guaranteed to be cruel every single time (all other methods), I'd pick the one the one where cruelty is only a possibility, rather than a guarantee.