Reskinning the Lord of the Rings

DisclaimerThis was just my best guess as to where such a thread would go.
If another section is better, please by all means, move it there. ^_^'

The Lord of the Rings is a story with which every roleplayer worth his dice is familiar, and nearly as many have likely wanted to play or run at some point in their lives. The trouble is that, being a book, it has several elements that are inherently difficult if not impossible to convert into a D&D suitable campaign including but not limited to: a set plot line from which there is no deviance and as such cannot account for unpredictable player actions, characters of varying degrees of skill (the hobbits pretty much all start as 1st level or thereabouts, Gandalf is easily an epic-level character, while the rest of the Fellowship are probably all at various points in the paragon tier), characters of varying plot significance (while in an ideal D&D campaign each player is of more or less equal importance), and so on.

To use a somewhat gruesome simile, most of the time trying to rework the Lord of the Rings to work as a tabletop campaign is like removing the skeleton and trying to force the skin and flesh to fit over another skeleton that differs both in size and shape. The outcome is a grotesque charicature at best. I've come up with the thought instead of basically stripping the story to its skeleton and rebuilding from that. Ideally, the outcome would be such that from the building blocks one could transplant the basic campaign from a generic D&D setting to Faerun to Eberron to Dark Sun to even another tabletop system altoghether with little more effort than switching out place names, environments, creatures and (if applicable) converting system rules.

I believe I have determined what the basic steps required to do this would be and they are as follows:
  1. Identifying the key events of the story. In addition to breaking down the story to its basic time line, it would be necessary to identify what the significance of the event is so that it can be transplanted between the various settings. For instance, an identified series of events may be entering the Mines of Moria; exploration; goblins attack (they have a cave troll); balrog shows up. However, is it really required that the party go through underground mines? Could they have to go through some other dangerous terrain like a swamp, desert, or wasteland? Does the creature that scares off the goblins need to be a giant firey demon? Does it even need to be a creature? Would volcanic activity not be just as effective for an underground setting? Or a vicious sandstorm in a desert? Do the goblins need to be goblins? and so on.
  2. Identifying what role each character (both in the Fellowship and out) bring to the table. Who are the characters and what are their roles? Which roles are necessary? Whose roles rely on other characters (e.g. Arwen has little purpose without Aragorn)? Can any roles be combined or removed to simplify the number of NPCs the GM must manage, or the number of players in the party (which is what makes the previous question important)? One of the most important questions (which combines with the point #1) is how to deal with party formation. In the book, Merry, Pippin, Sam and Frodo start off together and quite a few events unfold before Aragorn joins, followed by more events before the rest of the gang join in. The campaign should allow all of the players to start adventuring together, and allow everyone to play the character they want all the way through.
  3. Splitting the party. In the Lord of the Rings trilogy the party is split multiple times. At one point we have Gandalf and Pippin at Minas Tirith, Aragorn, Legolas, and Gimli traveling with the Rohan army, and Frodo and Sam traveling to Mordor (with the two of them occasionally being separated now and again). Should the party be split in a similar fashion? Assuming the average party size of 4 to 5 characters how would this be managed? Could events be shifted around or reordered to allow for the entire party to stick together thoughout (at least most of) the campaign?
  4. Miscellaneous backstory elements. Can or should the Ring be an Amulet instead? A Diadem? A Sock(s, pair of)? How was it made (since a volcano in the middle of a vast and foreboding wasteland isn't readily available in some settings)? Who should get the Ring and what should its powers and drawbacks be? Really, most of these should be answered by the GM (particularly who gets the Ring) as they will change from setting to setting, GM to GM, and party to party. Still, a handful of suggestions would likely be useful.