I've been routing a run that gets all eleven hats on the antique hatrack in the final cutscene. Your first hat (Barely enchanted, four-gallon, or floppy derby), the bear/cat/owl hat (when you click the name choice animal), the fake pope hat, the really nice cowboy hat, the prototype stetson, the turnip crown, the gold tooth crown, the yeast covered hat, the strange head sack, the spittoon hat, and the El Vibrato crown. So you do need to contain Roberto, but I've found a couple interesting skips. You also need to grab the necromancer crown to give to Norton, since everything else is on the hatrack. I've been using Alice because she has good skeleton encounters and she has the skeleton one-shot skill for the fake pope hat. All of her locations are places that you need to go to anyway. I've been using the beanslinger because Great Northern Blizzard works so well to grind for gold teeth. My route gets a few specific items for the stat bonuses to get into el vibrato locations on the coast. My current PB is 1:01, but I'm sure it can easily get under an hour. Especially someone who is better at mashing than me. I can post the vod if anyone would like to see how mediocre I am so far.