Putting Earth stance as a mini tank is kind of useless as a majority of content it's either not needed, or if it is you're already screwed. If straight effects it should be no knockback when on, but no damage buffs. So it's something you want to switch in and out of. Wind suffers same issue that, alone a temporary move speed buff is not needed because you can just sprint for the short time you need it. Fire giving crit rate is a good idea, I'm just not sure what wind would be. I'd be apprehensive of two different damage buff stance like wind giving attack speed because someone will crunch the numbers and the worse of the two will again never see use. It would need to be something that would actively be used in raids and trials, but also not overstep what another stance already does.