Thanks for the advice - I do 1 & 3 and I think I do 2 & 4 although that's less true when writing things with symbols (such as code), or when navigating text (I don't use vim). According to monkeytype.com, my typing speed is ~40wpm, which is apparently around average (not average for monkeytype users).

Thinking time definitely dominates, I'm hesitant to write something unless I'm confident in it, which I feel serves me well when writing code, but less well in other contexts (except perhaps HN, which has an unusually high fondness for accurate rebuttals of minor technical points). I spent ~20 minutes writing each of my 3 replies to you (longer on this one now that I've finished it). Perhaps being able to type at the speed I could talk would deny me the chance to think about it while waiting to finish typing, speeding me up indirectly.