Going to start off by saying I'm a Braves fan, so even though I may know more about the Braves players, I might be a little biased.
I love Freeman for his value. He's a low draft pick, and I don't think it's unreasonable that he puts up 25-30 HR while batting .280-.290. I don't think he's going to have a sophomore slump, because when you look at his minor league history, he generally starts off slow and then adjusts and heats up (which happened last season, started off slow, but finished strong).
I love Prado as a player, but I'm not so sure fantasy-wise. I have no doubts he's going to hit .300 (or close to it), but he's not going to hit over 20 HR, nor is he going to steal a lot of bases.
I'm not a big fan of Melky, and would consider starting Willingham (I assume you mean Josh Willingham, since I've never heard of Josh Williamson) over him.
All that said, I think you might need some more power.
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