Re the Dock: it may not be easily discoverable, but you can resize the Dock by hovering over a vertical bar between icon groups, then dragging up and down. Hold down the Option key to snap to (what I presume is one of a number of) unscaled icon sizes.
One of the first things I do on a new install (as well as turning on the Finder status bar) is option-clicking on the Dock and shrinking it down by one step (or maybe two on a 13" MacBook).
One of the first things I do on a new install (as well as turning on the Finder status bar) is option-clicking on the Dock and shrinking it down by one step (or maybe two on a 13" MacBook).