KLRBAER, glad to hear you've had such good luck with your trailer. I thought for sure the bicycle wheel would hold up for me as well, but it just couldn't take the off road abuse. I imagine your's is working so well becuase, as you mentioned, you mostly use it on the road.
I ride a dual sport that is mostly a dirt bike. Unlike your KLR, my bike isn't that great for the road, it can do it, but it's not that comfortable at it. That being said, my goal for a trailer was one that can be used mostly offroad, as that is the riding I enjoy. My trailer needs to able to handle single track riding and not make me slow down all that much. My vision is to ride into a camp spot, set up camp, ditch the trailer, and play around on my lightweight dirt bike. Sure, I could do the same with saddle bags and racks and such. However, the trailer comes off by removing one bolt (no tools required) and I'm back to the lightweight nimble dirt bike that I love.
We all have different requirements of our gear, if someone else happens to share my requirements, I'd enjoy building a trailer for them too.