I have the Charm, as well. I've found that I can stash a very tiny paperback in with the water bladder, but that's it. I have a bigger one for day trips but I don't really use it on the bike.

I would never put gatorade in the Camelbak, but I do fill it with ice if the day is hot enough. We tend to ride in hot weather so usually I have two bottles of Gatorade plus water in the Camelbak.

And cutting the hose is brilliant! I am going to do that before my next ride.