I'm with you, when they "reinvented eladrin" they just brought them into line with my mythos anyway.
Main elven race was "forest elves". Some xenophobic "wood elves" in the wilder lands. Mixed into the elven population were "high" elves or "eladrin".
These eladrin were the elves that had started to turn fey, or become one with some ideal. As such they were respected and honored, mainly becoming elven royalty. They were a fey stage of the race before/between the Eladrin of the higher realms.
Using an almost Raymond Fiest like concept; wood elves could turn/transition to eladrin, and in fact, drow elves could return to the light and turn into eladrin, being redeemed in a mystical journey back home to the elves. (such drow could be recognized, and were forbidden to be slain as while on their journey back to the light.) This drow part of course, was a deep elven secret.
Other elves could become one with the forest, or reach a higher plane, and sail to the islands of Arvandor.
So my elves are very morphic, in relation to their spiritual state and dedication to a principle. And when WotC brought in eladrin....they fit perfect as the inbetween the main elven race and the mystical celestial eladrin of the higher concepts.
/sorry semi tangent