My picks -
1) Improve the most: Kim Clijsters- She's only 18. Think how much better Venus is now than three years ago. Her play can stil lbe uneven, winning Hamburg, losing in Berlin first round. Shades of Venus in 2001 (winning Hamburg, 3rd round loss at Berlin). Her performances are uneven. Typical of young players. Three years from now, she may well be better than Venus is now. (Relax Williams fans, Venus will be better too.) Kim does get the yips at odd times, but experience and maturity well help that. She's gonna get better by growing up. The process might be slow, but, barringinjury, its sure.
2) Improve the fastest: Serena Williams. IF she improves. Nothing against Serena, but she plays like she's a winner machine and all she can or has to is hit the 'on' switch. (Makes you wonder if she and Justine are the actual sisters. They just can't help themselves sometimes. It;s just 'see it, kill it' with them most of the time.) Serena's got to learn to rein it in. NOt all the time. Not even most of the time. But against Schnyder at Charleston, Serena looked like she COULDN'T hit any way but allout. It was like she fighting herself. And losing. If Serena can correct this, her perfromance will improve fast. (Not that her performance isn't incredible.)
3) And who's going to be challenging Kim in seven years, when Kim's only 25 and the rest of the current top ten are either as good as they'll be, or going downhill?
There's a chance the rivalry in 2009 wil be Clijsters vs Daniela Hantuchova. Daniela's got a top fifteen body (See Venus, Meghann, Elena D), a good support system and a great attitude. Growing up will bring consistency. Like Kim, she can't really help BUT get better. And she already has some confidence, with a Tier I title and a victory over a top five player.