Why does Logic Pro have so many different keyboard shortcut tables?
Logic Pro's key commands are organized per window and editor rather than one flat list. Global commands work everywhere, but the Mixer, Piano Roll, Step Sequencer, and each of the other editors have their own additional key commands specific to what that window does.
Are Logic Pro keyboard shortcuts the same on Mac and iPad?
The core transport and track-editing shortcuts match. Mac has a much larger set overall, covering every specialized editor and window (Score Editor, MIDI Environment, Sampler, and more) that iPad's simpler interface doesn't expose via keyboard shortcuts.
Can I customize Logic Pro's keyboard shortcuts?
Yes, on Mac. Option-Command-K opens the Key Commands / Command Editor window, where you can view, search, and reassign any key command. The pages on HKeys cover the default key commands.