As the topic says, I'm interested to know if there is any mods that adds ren's mystic elves into the game.
IE. with lore, the rare npc, random dialogue references from other npcs, quests involving them, etc.

I'm also interested if anyone has elaborated on the basic lore that ren provided in the race description?

http://www.tesnexus.com/downloads/file.php?id=22320 sort of meets that criteria in that the author based his Ayleid race on Rens Mystic Elves, I believe.

That looks like an excellent mod. I'll have to try that one sometime, thanks.
That's very close to what I'm looking for, but I'm actually looking for stuff that integrates the mystic elf race itself into the main game.

Integration requires Race Balancing Project--which is actually the mod that adds Mystic Elves into the game. (RBP calls them 'Hidden Elves', and provides weasel lore to explain their existence.) It also includes optional plugins which integrate its extra races, by replacing certain standard race enemies and npc's. So if you're a Hidden Elf or Ohmes-Raht, you may find yourself meeting and battling others of your race from time to time.
Integration (basically a quest mod that also requires LAME) takes it a step further in that its npc's recognize you as the non-standard race that you are, and address you based on their own prejudices--which is way cool.

Aha, I didn't realize that RBP did so much. I thought it just adjusted the birthsigns and the races starting attributes.
I actually meant to download it and check it out before I started my char. I'm pretty far along now.

Anyhow, the reason I was asking is because I was considering an idea for a mod that adds quests and lore for them.
Also a mystic village hidden in the woods, that can only be visited by invitation, when you have a chance encounter with a native mystic elf.

I guess it could work with hidden elves instead and I know RBP is quite popular, so it would be best to work from what it has already established.
Integration looks great, but it's a bit contrary to the concept I had in mind. Ayleids are supposed to be extinct.
I'll have to investigate the lore that RBP has set.

My thoughts were that mystic elves are suspected to be the closest known relative of the ayleids, although they are different enough in culture and creed to be distinct.
If the ayleid are not actually extinct, their numbers are extremely few and any sighting of one would be huge news in tamriel.
The mystic elves on the other hand are known to exist, but are rarely seen.
They were ayleid's at one time, but wanted no involvement in the altmer conflict so they split into two separate factions before the war.
The mystic elves left the underground temples and constructed their own village deep in the great forest where they have prospered, mostly undetected for many centuries.
The village itself resides within a pocket they created between tamriel and the astral plane using the power of the varla stones.
Most everything known about them is based on legend, although as time goes by and their population grows, their village is getting too small to contain them all and some venture out to live among tamriel.

I'm probably getting ahead of myself here. I need to check out RBP first ^_^