Hrm....could even do the Moon Letters with the phase of the Moon or with different Lat/Long or Alignment of stars & planets so that X, Y, and Z Moon Letters/Instructions are revealed at different times and still be plausible ("Well, I could read the first set of instructions, why couldn't I read the other bit?!")
As for making magical items. I've had a Mage for ~10 years now who makes magical items along with another "rival". Each time that we make an item, it is specifically for Character X, Y, or Z. Lower level gear could be for everyone, but normally the Epic Level or near Epic Level gear is all "personalized".
I normally put it a "twist". "All the power in the universe, itty bitty living space!" Sure, they now have a +8/+8 Scimitar forged by Vulcan, but outside of Olympus it's "only" +3/+3 (my original DM put that into effect, I carried over the tradition). My Plate de Tarasque (spelling?) armor will drive non-Chaotic Evil characters insane - stuff like that.
But, if you're just going for subtle effects, I think that a personalized touch would be a very nice touch indeed. Perhaps she could forge gauntlets that boost Armed Combat by +1, but reduce Ranged combat by +1 (ever try to draw a bow with a gauntlet on?!). Bracelet of Grace (Nimbleness in LotR/Dex in DnD) of +1 to Nimbleness checks when not in combat (for a Rouge/Ranger type character set). Just some stuff that I would put out there to characters if I were the DM.
Good luck - I like the idea!!!
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