...or...just had another thought...what about a chenille wound around the shaft of a pheasant tail? (Just thinking a turkey feather shaft or peacock tail shaft might be too stiff,.) That feather shaft should give it some stiffness, while allowing some movement when slowly retrieved?

Although the chenille when wet might be a bit heavy. The feather shaft not very durable (would probably break when you set the hook), but would provide the stiffness while remaining lightweight.

OK...maybe overall NOT a good idea?

I've got some titanium leaders I use for pike that might give some action and durability, and also doesn't kink. Wrap one of those with chenille.
Or just use a very STIFF monofilament line for the core beneath the chenille/feathers/leather/bugskin?