While cruising the WCI forums the other day I was reminded of a finish I have not used in years that holds excellent promise for use on carvings. This one's gonna take some work, we have to mix it, and some extra materials, but I think it's worth it. We'll start with the recipe:
Polyurethane, spirit based, not the water based kind
Mineral spirits (commonly called paint thinner too)
Mix equal parts of all three items.
We're gonna get a penetrating finish that hardens in the surface of the wood, and leaves a nice oil patina. It offers more protection than the oil alone, imparts a nice low luster shine, enhances the grain, but does not build on the surface like the urethane alone would.