I used to find that flare height was the biggest issue, sorted as was suggested above by a long look at the relationship of the aircraft and the view from the ground with the aircraft in the landing attitude if possible; the other was a fixation on the instruments, but a chart draped over those took that out of the equation. A great number of the crew I fly and have flown with over the last 28 years in the airlines have no interest in GA flying, which saddens me, as the potential to accumulate hands on stick and rudder time or even the wish to do so diminishes with every year.
I regularly fly a Cub as well as the airliner and will continue to do so because it is fun.