I have used everything from shovel handles to PVC to get out on the water. I find two things that help me grip smooth surfaces, good gloves and diameter of shaft.

There is a fiberglass twist lock adjustable that is designed to use as a paint roller extension. The push button roller extensions are trash. The twist lock is a little thicker than most tillers and gloves grab it well. Plus it will not corrode and is non conducting.... something Florida sailors are always concerned about.

As was mentioned before, if the rudders and mast rake are set correctly, it is almost like power steering. Unless a rudder pops up and becomes a lever, there should be easy grip enough to hold it in your teeth for the most part.

It is the fine point of weather helm seeking to turn you up wind or raked where the cat will leave you stranded and sail on if you fall off. Since I do not race, getting worried about advantages of weather helmed set ups vs ease of operation tends to lead to the more comfortable choice.