The proper offset relieves strain on the wrists and elbows. Sea kayak and touring paddles are cut at 70 degrees, unless requested otherwise. This a compromise for wind resistance. Each shaft is customized to expected work load. Wood shafts load and unload more efficiently, creating less strain on the elbows and shoulders.
Shafts are stringer lay-up with oval indexing.
Blades are triple banded with extremely durable hardwoods. A solid fiberglass tip is overlaid with fancy veneer or marquetry. After the shaft receives its coats of deep penetrating epoxy, the paddle is ready for varnish. I could go on and on about sanding between each coat or book matching the whole tree. How to perfectly balance a paddle or using rot resistant wood, etc.