Re: Ana Ivanovic's ball toss
I have her serve mechanics, and I know that it's really hard to keep that ball in the same spot, so I altered mine slightly to not take my arm so far down and up, keeping it more level. I feel like that would help her tons. She also takes advantage of the fact that she has a very flexible shoulder, and she hits a lot of tosses anyway. Bad habit breeds bad trait.
Serena , Venus , Petra , Ana 
Simona, Vika , Angie, Sveta, Garbiñe
Kim , Mahree , Monica , Dokic, Sandrine, Jie