If the Flyers decide to add a defender via free agency, I hope they target Nikita Nikitin in Columbus. The guy is a solid defender and has shown that he is capable of running a power play and has some offensive pop to his game. He's also a very good and smart defender that doesn't do anything stupid and always makes the safe play.
I honestly don't know if they should go after a forward this off season. As much as I despise Hartnell and wish they'd ship him out to Siberia, there's no other left winger on the market that would be able to replace him. Vanek is going to be incredibly expensive, Moulson thinks he's a superstar and as such, wants superstar money and Callahan simply isn't an offensive left winger. I like Cammalleri, but if you look at his career, it's been a trend of good season followed by bad season.
At this point, it might be best for the club to start working in younger players like Akeson, Alt, and Hagg. Add possibly Scott Laughton and Shayne Gostisbehere to the big club and that's five young players that they'll need to make room for.
This is the opportunity the club needs to continue the retool of the franchise that should have been done after the season from hell (06 - 07). Continue working these younger players into the lineup, give them an opportunity to have an impact and force some of the overpaid veterans to step up their game.