Eckhard, the 738 seems to be very slick, and it doesnt look like there is an appreciable effect...while the heavies, seem to want to float there, especially looking at the FAS of the B748/A388, looks like you have to push them down or they would keep gliding.
Underfire,
I remember a training video which showed the PFD of a 747-400 sim being manually flown down the ILS with manual thrust. Of course, being a sim, everything was 'perfect'. At about 400ft the pilot let go of the controls and the thrust levers. The aircraft continued on the GS until about 200ft when the VS started to reduce slightly and the GS diamond began to drop. I think the aircraft crossed the threshold at about 120ft.
The training point was that yes, you have to keep 'pushing it down' to maintain the GS.
As far as strong winds and different flap settings are concerned, I don't remember any noticeable difference.