For a long time I wanted a small wheel to learn tricks but I didn’t want a trials uni. I figured the tire would be overkill for the light hopping I was mostly interested in and too heavy to learn basic freestyle skills. I looked at building a custom 20" wheel with a wide rim and BMX tire that would be somewhere between a trials and a freestyle (kind of like the KH Flatland wheelset that’s supposed to be coming soon).
In the end I bought a trials uni. It turns out that the wheel isn’t too heavy for learning what I want to learn (riding backwards, one-footed, wheelwalking, etc) and I really like the size of the tire for bouncing. I may still eventually build that BMX-like wheel but I’m not sure how much use it would see. The trials setup really makes for a very versatile uni.