I understand very well that often translation from one language into another means losing some of the subtleties and flavor inherent in the original language. However, successful translation is not about being able to reproduce words with absolute accuracy, but rather being able to represent context and meaning perfectly. Oftentimes in trying to get exact wording or phraseology something more important is lost; the exact significance, sense and message. This is where the skill of the translator comes in, knowing and being so familiar with the languages he or she is working with that like breathing, he/she is able o travel easily to and fro the different languages.
In the case of these words: Mark vs. Graven, in a sense it is irrelevant that the word was not translated exactly from the Greek as you noted. Consider the definition:
1. old use
Carved or engraved.
2. Firmly fixed in the mind.
Etymology: 14c: from old word grave to carve or engrave.
It would have been plainly obvious to the Bible translators that a carving or an engraving upon a hand or a forehead would serve the purposes of "marking" the individual. Therefore this carving or engraving would be exactly that, a mark. What is important to notice is that a "carved or engraved mark" gives the sense of something that is quite palpable and physical, and not of elusive or esoteric essence, as in a spiritual condition.
Another thing that is important to glean from this little excersice in transliteration, is it gives us something to think about in terms of what sort of mark would the system of the Antichrist be forging on people. Will it be an implantable chip, as many suggest, or some other method of branding humanity? It makes speculation all the more difficult, but gives us something to think about.