the only 'float' was via my aching knees
I think you can get a bit of float, it depends on how wide the slot in the shoeplates are. If the pedal is a tight fit, you could widen the slot slightly or shape it like a very flat X shape.
it takes a good deal of confidence to yank up the straps good and tight
I guess it's the thought that your foot is locked to the pedal until you can reach down and release the strap. But I think in practice, in an emergency you either have enough time to flick the strap or you haven't and you're going to down anyway.
I wouldn't have wanted to try to get my shoes back in the clips after a hill start
Tap the back of the pedal (tab) with your foot to flip it up and insert foot, or pedal on the underside for a few revs.
wooden soled cycling shoes are not very forgiving
A thick insole might help with comfort.
You don't see many sprinters coming adrift from their pedals these days
But track sprinters do use toestraps with clipless pedals.
I think by the late 70s, cycling shoes usually came with their own built-in adjustible plastic shoeplates. Before that, you had to use nails to fix metal shoeplates to the soles.