I think it depends on the looks of the knife. Of course, to me, leather washers, wood, stag, ara all god materials for a traditonal fixed blade. My old Case Official scout sheath knife was stacked leather washers. But my old Randall 14 was black micarta. The Randall was still a nice looking knife, but it wasn't all that traditional looking though.
I have a old Swedish Frosts mora number 1 with the wood handle. The red paint was sanded off and the birch finished with linseed oil. It looks like something that could have been carried a century ago. On the other hand, my old Buck 102 woodsman has a traditonal profile and looks, but the black micarta handle makes it look modern. Because of the slick finish, I roughed it up with 220 grit sandpaper, and that brought out the cloth pattern in the micarta, making it look a bit more rustic. Over all, the rougher finish on the micarta gave it a more old timy look. If you have to have micarta scales, then let the weave of the material show through. Don't polish it off, leave it rougher.
Carl.