If a classic rifle go traditional. Ebony grip caps look great with a small ivory diamond and are still within the classic mode. A small diamond on the fore end checkering and grips can look good too. Much beyond that it could go bad quickly. Now on a Weatherby or Winslow rifle knock your socks off.

Me I would use those materials on knife handles and not monkey with good taste on the rifle.

"When you disarm the people, you commence to offend them and show that you distrust them either through cowardice or lack of confidence, and both of these opinions generate hatred." Niccolo Machiavelli