Basically you have a choice between semi-metallic, which is probably what's on there from factory, or ceramic. There are a couple of others, but these are the most common for typical use. Ceramic is reputedly the best, though you'll probably struggle to find any real proof of increased performance. The big benefit of them seems to be far less dust, less noise and long life. I've used ATE ceramic pads in the past, though not on a T6. They worked fine with very little dust as advertised, but even ATE themselves make no claim of increased braking performance as such.
As van is nearly near twice the weight of the Passat and running on the same diameter rotor, you'll need a more complicated mod than changing pads to bring it's braking characteristics even close to how the Passat feels. Either increase the brake pressure or increase the size of the rotor.