Problem is that there just aren't that many PFs on the market that would be a big help to the Bucks. Shareef Abdur-Rahim would, but it looks like he's headed elsewhere (looks like he wants to take the MLE from an immediate contender). Tyson Chandler would, but he's out of their price range. The only guy that might have made sense and is available is Stromile Swift.
I suppose Swift would be a better pickup, but I'm getting the feeling that he's going to be dramatically overpaid by someone. Call it a hunch. In any event, aside from that, the 4s on the market won't help the Bucks much. You can get by with Joe Smith and Dan Gadzuric at the 4. It's not ideal, but they're not bad. Remember that Gadzuric frequently was pressed into service at center last year, which he's ill-suited for. He'll be better at the 4.