Personally, for towing, I'd go for semi-metallic type pads. More bite even though they tend to make a good amount of dust. They also don't last as long as Ceramic brakes.
Ceramic pads are great for lighter duty vehicles. They don't dust as much and have a far longer life. But they don't have nearly as much "bite" as a semi-metallic would. I've noticed on my wife's old Subaru, when I switched her to Ceramic, it took a little more effort to achieve the same stopping distances. I'm taking it that this would not be desirable for a Tow Vehicle :).
Generally I avoid organics. This is just the bottom-of-the-barrel choice in my book. Doesn't last as long as semi-metallics and doesn't bite as hard given its shorter life.
Also, no need to replace your rotors right away. I don't know what your rotor costs are, but for 5 or 10 bucks a pop at the local parts store, I have always turned mine. There's a spec for minimum thickness on the rotor before they're condemned and I like to maximize the life out of them. I've never had a turned rotor crack on me in my lifetime.