Basically, the Cardinals were largely built internally, but they spent good money on outfielders - Matt Holiday and Carlos Beltran. The Red Sox have certainly had their development success stories (Ellsbury, Pedroia, Bucholz) but relied more on the free agent market.
The number that I think is most important is $83 million. That's the number the Red Sox spent on 2013 contracts through free agency. Filling multiple needs simultaneously through free agency is expensive. Yes, the Mets have many needs - most notably in the rotation, in the outfield, and at short stop. In fact, I would argue that it is beyond the Mets' budget (whatever that budget is) at the moment. Moreover, as Michael Baron pointed out two days ago, the Red Sox had a better base of proven, returning talent in 2013 than the Mets will have in 2014.
Put simply, I believe that the Mets have too many holes, and not enough money to address them all at once this offseason to become a playoff caliber team in 2014. (Unless, of course, the Mets have $80 to spend on 2014 payroll, and that strikes me as wildly unlikely.) Instead, the team should be focused on acquiring cost-controlled talent, so that when Harvey returns, and their talent base is closer to playoff level, the Mets can find their own Victorino, Holliday, or late-career Beltran.