Another really problematic thing: the hotkeys for "Step Forward / Backward 1 Frame" don't actually operate in frames. They operate in whatever time units the Timeline is set to. So, if the Timeline is set to Show Audio Time Units, the hotkeys only step forward or back by one audio sample. How is this helpful?
Apparently, if the Timeline is set to Show Audio Time Units, there's no way to snap the current time to whole frames. Dragging the edges of clips does snap to frames, but when clicking in the Timeline to change the current time (location of play head), the cursor only snaps to audio samples.
Really, the limitations of the Premiere UX just defy all rational expectations. Compare to Vegas, which has no problems A) zooming in to arbitrary levels of magnification, B) snapping to whatever the user wants to snap to, regardless of anything else, and C) accurately displaying continuous thumbnails.
Really, Premiere is just such a huge disappointment.