This is an interesting question.
My prior experience with planers has been two Scheppach/Ixes models that have rubber coated feed rollers - these work tremendously well in that they grip the workpiece effectively and leave no indentations in the finished surface, regardless of how fine a cut is taken. I believe that the Schepoach rollers are patented, but even so I am surprised other manufacturers do not offer them.
More recently, I have bought an Inca planer thicknesser that I use on my never-ending away project. I rebuilt the machine top to bottom and it is very nice to use.
However, it has a serrated infeed roller that does not grip as well as the rubber Scheppach ones. The springs in my case are well tensioned. The points of the teeth on the roller do appear to have been worn slightly and no doubt a new (££££) roller would help.
I have wondered whether it would be possible to engineer an adaptation to a set of Schepoach rollers to fit to the Inca. I have not yet compared the drive sprockets and bushings etc, but I think it would improve the Inca machine.
Might be worth thinking about for other planers.
Cheers