I like the UI of both Elektron devices and Push 3 and think that they are both well thought out. They both flow very well for me. If I had to pick one knob placement, it would be Push, because the knobs are directly over the parameter you are adjusting. And I don’t have any issues with my arms covering the display.
Another thing to consider is that on an Elektron machine, the majority of the time you are bouncing between the same handful of pages, so the knobs quickly become muscle memory. This is because each Elektron box is a focused instrument. Push is more vast in those regards, where you can have one track being a synth, one track a sampler, you can have many fx per tracks, racks, and so on. And I think for how vast Push is, they did a very good job with the UI.