Stiletto,
The SS blades will 'hold value' at least as well, if not better than the carbon steel knife. As Randall's continue to head more into 'collector' territory, actual use value becomes somewhat secondary to 'options' value. Stainless steel is an option, and many folks, both buyer and seller alike, will add up the value of the knife based on the various options included.
Re: Embellishment; engraving, scrimshanding, inlay's etc. are a personal preference, usually only adding (substantial) value to the knife if the work is done by one of the recognized (authorized) RMK embellishers; or, if you can find a buyer down the road with similar tastes...
That's my .2 cents worth anyway, and worth every penny that ya paid...lol
Hope that helps,
Shel
p.s. The military collectibles market is much larger than the knife collecting market, if an item (such as a knife with military provenance) crosses over into both markets, then there's a larger base of potential buyers, which usually drives the price up accordingly...