Agree the higher the eye line the better. Makes a big difference in Cessna Cardinals.
Reducing work load on approach makes a big difference.
Being in trim, on centre line,correct approach speed and glide slope early gives more mental capacity for the flare. One other trick is get your instructor to fly down the runway in ground effect. Helps with learning the correct flare and hold off height with time to learn what it looks like.
Most instructors teach to reduce power and raise the nose a little when crossing the hedge, this is extra work load at a critical point that can upset you and I believe teaches bad practise for landing heavier aircraft in the future they generally develop high sink rates if this is done, not good.
I believe the best is leave it alone until the flare point, flare then close the throttle and it will slow sink on to the runway. Does make instructors jumpy but works well, but don't flare late.