I am 3d6
In board and card games there seems to be a spectrum that runs between simuation and abstraction. On one end there's stuff like the old Avalon-Hill wargames, while at the other end there's (for example) Cheapass Games' Brawl, which presents itself as a fighting card game but is mostly about matching colors. I think video games can be looked at in terms of this spectrum too, even within a given genre (Gran Turismo and Mario Kart are two very different racing games, for example).
But what about roleplaying games? The kind of abstraction I've been talking about mostly comes about as a result of making creative use of the medium itself; a game like Super Mario Bros. probably wouldn't have come about on a game console more powerful than the NES, with sprites limited to a certain size and a definite need for reusable scenery and enemies. In D&D the basic combat mechanic is based around the abstractions inherent in how its hit points and ACs work, and this in a very combat-oriented game ("kill things and take their stuff"). The intent there I suppose was to streamline things -- having all the dodging and weaving implied means that a single d20 roll can resolve whether or not an attack hits well enough to do damage, which is overall pretty nice.
A newer and IMO more interesting example of this is in Eiyuu Sentai Seigiranger (from the TRPG Super Session Daikyouen RPG anthology I ordered from Japan). Since it's based on sentai shows it naturally includes "mooks" (the equivalent of Power Rangers' Putty Patrollers), but they're called "dicemen" and each has a six-sided die for a face that actually shows how many HP they have left. This is overall pretty silly (it helps that Seigiranger is pretty tongue-in-cheek) and it shoves the game mechanic directly into the continuum of the game's shared world, and yet at the same time it's a stroke of genius. The game uses playing cards for action resolution, and the dicemen transform the six-siders into a combination prop and play aid.
I'm not saying it's an inherently better approach, but I wonder what it would be like to specifically try to build off of the medium of roleplaying games to the point where realism/plausibility with regard to other media is diminised. Granted, it's probably in the nature of RPGs that this is hard to pull off well, owing to the medium's general attitude towards story, but the possibilities are intriguing.