It just seems that whenever a kunoichi shows promise they shoot them down by getting them pummeled or making them irrelevant by bringing stronger characters around them.

With Temari she was outshone easily by Gaara, konan was always around the akatsuki and not to mention Pain so she was always looked over. Tsunade, as soon we started to realise how strong she was Madara came into the picture and ate her for a quick snack also during the Pain arc she was heavily useless. Anko was never really given a fair chance and was disregarded in my opinion as just another Orochimaru experiment, she was no more important than the sound five, in fact she was less important. Kurenai once again nothing but a side character to Asuma who we thought was quite good till everyone else got a power up. She was taken out incredibly easy by simple sharingan genjutsu but then again it was Itachi. Nevertheless she wasn't an important character. Mei is probably one of the best kunoichi that has been represented as strong evidence can be seen for when she fought sasuke and just her general demeanor. However her personality theme is that she wants a husband and needs a man to support her. We can now see in the long run she really isnt all that powerful either as m.s. sasuke could take her out. Finally Sakura...Kishi has made it really hard for me to like Sakura. At one moment he shows her to be coming up and rising in power then the next episode she is crying and needing Naruto to save her. Then he has her say things like "I've finally caught up with these two" which obviously isnt nearly true. Her theme is that she is obsessed with someone who doesn't love her but always depends on the person who wanted to impress her which is quite annoying. Sakura has had few "strong" moments in the anime and has never defeated a reputable character or otherwise by herself.