I think the Pats should try and trade Fells now for some minimal consideration if they can get it, because realistically I don't see the value of keeping him on the roster if they re-sign both Ballard and Hoomanawanui. They won't likely carry more than 4 TEs, and Fells was behind Hooman on the depth chart. Cutting him frees up almost $1M this year, and $1.85M in 2014.
Your 2 restructurings would free up $5.5M. Add $1M from Fells and you have an additional $6.5M in cap space, which might cover the 2013 cap hit of one of the 3 major re-signings depending on how the contract was structured.
I've also suggested that Gostkowski and Connolly could be candidates for restructuring or pay cuts. Both make over $3.3M this year and over $3.8 next year. That seems like an awful lot to spend. Both are fine players, but there may need to be some brutal decision making over the next month or so. I also wonder if they might try and tack on another year to Brandon Lloyd's deal and knock his numbers down some ($4.5M in 2013, $5.5M in 2014).
Regardless, I think the Pats have some work to do to manage their cap situation in order to move forward, and I think these kind of cheap depth signings are an important part of the process. If any one of them pans out, it works out great for the team.