alexandrite of course as you said. Thats besides the point as i haven't actually completed my animus weapon...nor has most of the free company i'm in.
the point is the cost has to justify the outcome, and i'm simply not seeing it. its like with atma where all it did was change the color and the item level (and nothing else) after hours, days, or even weeks grinding fates. this is the same bloody thing (or pretty close to it at that), where we do a ton of grinding for what? the option to make your artifact gear dyeable in pretty colors.
i heard a friend of mine gets around 1700 myth in about two days (he admits that he could get more if he had more time to do so.) so lets do some math
we'll default the augmentation parts to 2500 to keep it simple. (the bards set requires saurian leather, ancient lumber, treated spruce lumber, terminus putty, and hard hippogryph skin as a note)
17500 myth total for a fully dyeable AF set.
1700 over the course of two days means around 20 days to get the myth needed plus another to get 500 myth. (not taking into account that if you don't have multiple crafting classes at 3 stars, you then need to find a crafter to have them craft each individual part.)
so unless your sitting on an insane amount of gil, no life it or otherwise: have fun sitting on a massive content lock that would only allow you the option to dye a piece of vanity gear.
