I've actually gone the other way and made all magic items artifacts in my 13th Age game. The treatment they give in the core rules hints personality and gives basic features, but I've actually added three points of ego I suppose you can still call it, between positive, neutral, and negative in the vein of the old 4e artifact rules. I don't track positive and negative points or anything like that, I just sort of feel it out (the game is a lot about feeling it out organically). Even using one of these artifacts influences a wielder a little bit, though it doesn't have to be having a full-blown conversation with a talking sword like I think someone up top was against. It could be a vampiric dagger that has you fixating on blood, or Wort's wooden leg that makes it difficult for you to sell anything at a fair price...
In truth, it provides just another springboard for collaboration and interesting story.