I think there are some beautiful wood handles around. I've only seen bent handles on fly rods, but I'm sure it's been done before.
There's a mob called gondwana rods that makes some ripper handles in Aussie timbers.
Can't find the web site though.
or for a yankee site, try
http://classiccustomwood.com/Handles.htm
Not sure on the ergonomics theory. It would certainly be better at rest.
When casting & flicking the lure in retrieve you're going to use the full extent of your wrist motion anyway.
But at the end of the day, if it makes it 5% more comfortable to use, that's another 150 or more casts before you're too sore & have to go home