Re when to flare:
My old FIC instructor advocated beginning the flare "when the grass resolves itself from a uniform green appearance to where you can see individual blades..."
I never got the hang of that one myself. Perhaps we had different focal lengths. Looking horizontally, it gives me 80 to 100 feet.
That same instructor, now sadly departed, told of practising engine-offs to a hard runway in a Dragonfly (or a Sycamore, I forget). After a session he went back and told his superior what he'd been doing.
'Very good,' came the reply. 'But try raising the lever in the last six feet, it works a treat.'