Personally, I love dueling. It's certainly not balanced in the slightest, but it can still be competitive and fun and I enjoy hosting a semi-casual dueling tournament from time to time.

That said, I'd love to see more areas you can duel in. As discussed in this thread, that does raise questions of how you can make that work. Someone already mentioned this and I agree, the simplest solution to expanding dueling options would be to simply add a dueling arena to every major city. I like the idea of having a housing item that allows you to create a small dueling arena in your home, too! Now that would be cool.

I think dueling being available everywhere all the time is the ideal, however from a technical standpoint it's probably the least realistic. It would require a lot of code and probably a lot of network resources. Not sure though and I'd love to see it implemented.