I find some of the sliders for on/off are impossible to read. You can't work out what is on or off.
Windows 3.11 / 95 UI seems such a good idea by comparison to today's UIs - checkboxes with obvious tick marks or X marks in them, radio buttons, buttons that look like actual buttons, scrollbars you can see without having to flail the mouse around just for them to appear, scrollbars that go the right way when you use the mouse wheel (ok that was Windows 98), maximise buttons that actually maximised a window without having to hold alt like on macOS these days...