Keep the sunscreen and purell outside the FAK - everyone needs sunscreen, and everyone who cooks or cleans up after a meal should use the purell. I don't eat well unless I see the cook wash his hands on hikes...

On the Second Skin in lieu of moleskin suggestion below, that's the voice of experience for ya - I haven't had a serious blister myself since before you were born climberslacker, and any Scout along on a hike shouldn't have more than one, since before the next trip they get taped up (with duct tape) over their hot spots. Second Skin does sound nice.

Leuko silk tape? I'm not sure how silk tape is priced, but the latex leuko tape is pretty expensive, you could buy alot of kit for the price of one roll. REI sells a roll of good tape for a few dollars, Sports Authority sells a bulk pack of 5 x 25 yds ankle wrapping tape for maybe $10 (though it can be a little tough to tear off). Ankles tape up just as well with either, and cheaper.