Oh, how great a day it is indeed, when I pull up the forums and see a SHARK post at the top.
Well met, again, my good man.
Excellent analysis, as always.
Extending that analysis into the fantasy worlds we game in, in the Forgotten Realms, which my campaigns have called home for the last 20 years (yikes!), the elves therin do many of the things you describe. By observing the maps of the realms, the elves find themselves routinely in locations of vastly superior strategic relevance and defensability: Myth Drannor, in the heart of Cormanthor (the largest forest on the planet), Evermeet (a floating fortress, guarded by the most superior navy on the seas by miles), Evereska (surrounded by impassable natural hazards (mountains), forest, and desert, Yuirwood, an elven stronghold in the heart of a mystical forest. A campaign against the elves would (and was indeed) a bloody and brutal affair. Elven High Magic clearly holds the place of highest and most powerful and effective spellcasting the realms has ever known (with perhaps the one notable exception of Karsus). The elves wield moonblades, and reading through the Elves of Evermeet or Ruins of Myth Drannor, artifacts and comparable relics seem almost commonplace. They are the most powerful and skilled craftsman and artisans the realms knows. In the heights of Myth Drannor, and now Silverymoon, they combine this expertise with the dwarves metalworking and human innovation to create new generations of magical tools and tactics (Blast Scepters, Harps of Myth Drannor, etc.). The "common man" among eles clearly has access to more powerful equipment and weapons. The elite forces (and there are many, many elites) are among the most well equipped, best trained, and most capable forces: Arcane Archers, High Magi, Leaders of the Houses of Evermeet, the Bladesingers, the Elven Armada, Elven Knights (astride Unicorn/Pegasi). The elves live primarily in "natural" habitats, except where they share homes with humans and dwarves. Taking their lands would leave you with densely forested land, natural homes (which may wither and rot away when unattended), and those things the elves hold in highest regard: beauty, nature, love, friendship, curiousity. Not exactly the kind of thing that most nations would find worthy to mount a devastating and costly campaign to acquire.
Well played, my friend.