Tanking stances leave something to be desired on both tanks. As mentioned, PLD can't immediately go into a tank stance without waiting on MP or burning an MP item (if it's enough..). A WAR can't go into tank stance without "losing" the bonus HP from the tank stance (he starts off at 75% of his Defiance HP since the HP boost won't heal him). I think Defiance could just have it so that the % of your current HP compared to max HP would be applied to the amount of HP you heal up through Defiance when switching (ie, WAR at half HP when hitting Defiance would raise max HP by 25% and boost current HP by 12.5%). PLD is a bit trickier to balance, but honestly, I don't see much reason for the MP cost attribute of the stances. Either get rid of that, or just make it a set cost of "a maximum of X MP, and anything below that will be lost." IE, if it costs 200 MP to switch to Shield Oath, if the PLD has 500 MP he will lose 200 MP, and if he only has 50 MP he will lose 50 MP.