Didn't the Mattock of the Titans require someone to be at least six feet tall in order to use? I might be thinking of a different item, and I'd be surprised if they kept that requirement in 5E, but the principal still stands. The crunch is only valid because it accurately reflects the fluff. If you change the fluff, then you need to change the crunch to reflect that, or else it undermines the validity of the model.Which is true for the most part. For most people the order of importance is a factor. Spell slots are crunch first and fluff second because of balance considerations where the colour of a PCs hair is fluff first and crunch almost never.