You're still mostly right, but Colemak does actually move Backspace to the Caps Lock key, which is a change I'd recommend to every single person who types on a computer keyboard.
My understanding is that (maybe non-intuitively) whole hand movements are more likely to cause wrist-related RSI than single finger travels. (Single finger travels are more likely to create knuckle RSIs, certainly.) The missing letter in RSI is sometimes "movement" as it is stress from repetitive movements.
Anecdotally, the biggest mistake and the source of most of my pain from the way I had learned QWERTY was a lot of whole hand movements, and reducing those was a very clear and specific goal for me when I relearned touch typing (on Colemak).