Me, I agree 100%. I have been saying to my friends, why won't he do a Nam movie instead. It's was a crazy time, and with his mind, that movie could make Apocalypse Now look like G.I. Joe.
But after I.B. I would love for him to do a western or an italian horror type slasher, like a Dario Argento fillm. But after Grindhouse did so bad for some reason in the movies, I don't think he would adventure into much more of the "Grindhouse" style movies.