I would say.. tsunade or the mizukage , then konan (R.I.P), then sakura and other stuff because she has the potential of surpassing tsunade but shes not stronger yet.
Right now ... alive ... the most strongest female in Naruto is Tsunade , and I don't think Sakura is gonna surpass her because Sakura like Hinata havent improoved her abilites along the series so much ... I mean Sakura is not that strong ...
Tsunade, hands down. But with time, Sakura will blossom to be better than her Shishou. :3 Godaime Mizukage is also great. Konan is awesome too- she took out a majority of Tobi's mask, a considerably "untouchable" character.
I'd have to pull for tsunade on this one. She's badass lol. Mizukage is a close second but, tsunade is better, however, i believe sakura and temari will rise to be the strongest. Temari is already a badass, sakura's not too far behind. As for hinata, i hope she chokes and dies. ^_^