So it turns out there’s a whole, actually semi-USABLE system for cursor control and selecting text on iOS devices that I had no idea existed.
In any text-input or writing area, fist tap to move the cursor someplace in your text, then:
2 finger tap anywhere, hold the down tap until the cursor pulses bigger, and then drag to free-form move the cursor anywhere
double tap a word to select, then 2 finger tap (watch for the cursor size pulse) then drag the two fingers around to change the selection area
I find it flakey in Safari, which is too eager to drag the window. Ymmv. I’m still experimenting.