There is no need to wear an outfit to have the stats. You just need to unlock it. Usually cloths' stats are overpriced untill you are over 80k, this is why it's not recommended to buy them before that power. Ghost is the default page you would buy since it helps with the survivability of the tanks (HP), while giving additional stats to the damage dealers behind.

For your mood i would advise it this way:

Azure -> + hp - atk The only azure that matters, is the one still alive. Unless you're against amateurs, she is the first target.

Roshi -> + hp/nin - atk Enhancing nin will increase damage and scaling, hp is for survivability. It depends on how much power you have.

Sailor -> + atk/nin - hp Increase her nin for better heals and atk for scaling. Why less HP? To "trick" the AI in auto: she is much more likely to survive turn 2, with her regen, then your roshi before his scaling.