The display scaleing thing is nice but has been around a long time in some other software actually. The Unity engine had a similar feature going all the way back to 2015. It could scale automatically depending on the monitor size, even on a mobile device with support for 4k monitors and hDPI. I think Zbrush has the same kind of thing too. As far as custom UI's go, I think Blender has them all beat. You could literally redesign the entire UI any way you want from the ground up. Zbrush has a very customizable UI too, although I don't know if it's automatic like Unity and LW.