NADAC has a lot of classes he could probably do, and if you did want to jump him, you could end up jumping him pretty low. The highest height is 20", and you can do skilled at 16", when hes a senior you could go down as low at 12".
They have tunnelers/hoopers classes which dont have any other obstacles. Weavers is just tunnels, hoops, and weaves. Touch n Go is contacts, hoops, and tunnels. Jumpers is tunnels and jumps. Regular is all the equipment and Chances is a distance challenge and it can have all the equipment, but at the novice level its very limited, like 10 obstacles maybe. Their contacts are also very low, since NADAC is big on safety, or at least that is their claim as to why their obstacles are how they are.
They also just came out with something new (thats just now picking up momentum), its called EGC. The extreme games challenge, or something like that. It basically has gates (which they go out around). These challenges have no jumps, they are all gates, hoops, and tunnels and rely heavy on distance. I have not ever competed in it, but my club offered it once at a special training night. Here is a link if you wanted to see what it looks like. It was our first time trying it and Rush really liked it! (skip to around 1:15) http://www.youtube.com/watch?v=rD2C3zV3w98
When I read your post I thought of NADAC right away. You can still do agility but alter your goals. Maybe instead of traditional agility, Limit might be more cut out for distance goals with low impact.