We are not following the Pats model in the least...not even close. You can compare us somewhat to the Eagles, but the reason they can let good players go is because they are already a good roster. Were we already a solid roster, we could limit ourselves to surgical moves here and there to improve and maintain. As it stands, we have the solid basis for a good team, but the roster needs more bolstering than just one player here and another there. We're still 5-6 solid, immediate contributors away from being a top team, so unless you're content to fail to compete again, we need to be aggressive.
I need to expand on the Pats point. The Pats constantly sign aging players to augment their roster, counting on veteran ability to bolster their team. We do quite the opposite, and routinely discount adding a player due to age. The Pats are also routinely active in the offseason, identifying areas of need and filling them. Last year, they had a lousy receiving corps, so they added Welker (trade), Moss (trade), and Stallworth (FA). When was the last time the Cards were that aggressive in filling their needs through trades and FA?