Ultravids look like Ultravids. Punchy, contrasty, saturated, etc. There are of course differences in exit pupil and field of view which has an impact on ease of use and brightness. The 8x32 is not as bright as the 7x42 as you’d expect, and the “darker” view can make it feel a bit “punchier” and contrasty, but that’s a subtle difference and the overall character of the view through Ultravids in my experience has been remarkably consistent.
The focus knobs are all the same design. You’re somewhat attributing sample variation to model differences. My wife’s UV 8x32 HD has a nice smooth focus knob. I had a Zeiss FL 10x32 that had a fairly stiff focus knob that made fine focus adjustment a bit tricky. My 7x42 HD has a slightly stiffer/coarser focus than my wife’s 8x32.
So in other words there’s more focus knob variation among individual samples of a given model than there is between different models in the lineup. You could switch to a 7x42 and get a better focus knob, or you might not… and you could try another 8x32 and get a better focus knob. This is true for nearly any brand in my experience.
One lovely thing about the 7x is the depth of field makes fine focus easy — I find focus acquisition to be virtually effortless in the field. And since “fiddly” use is an issue, the 7x42 is about as “easy” a binocular as I’ve ever used — the combination of the ergonomics, compact form factor (a benefit ergonomically in a 42mm, not always for a 32mm), wide FOV and great DOF makes them so pleasurable to use. The 7x42 is really special.