Just to talk you off the ledge a bit, but the bolded is exactly how the Pats have maintained their success - of course they have Belichick and Brady as well. They don't throw huge contracts at players but rather fill out an entire rosters with good to very good players.
If Sam is the real deal then he should be able to turn receivers into stars and not need star WRs - look at the Pats, Green Bay, Seattle and Saints for examples. I know those QBs are all on another level - but the point is if the QB is legit, things fall into place.
The key is improving the o-line (which is easier said then done). While Coleman, McGuire and random rookie isn't much better than last season, it's more than adequate. Coleman has game breaking speed - and it all comes down to a better line and a better passing game.
Moncrief (or Humphries) plus Anderson, Enunwa, (a third or fourth round rookie) and Herndon isn't loaded but it's a bunch of guys that are good in their specific roles and it's an improvement over last season. It gives Sam talent to work with and it's up to him to improve his consistency.
If they sign a good CB to replace Skrine, Maye stays healthy and they add a stud pass rusher in the draft, with Gregg Williams's aggressive style this could be a top 10 defense.
The free agency rush is exciting in it's way but how many teams that win the offseason, end up winning in-season. It's not the way to build a team. I like Bell a lot and I still won't be upset if they do go out and get him - but I just don't think he'll make a major difference on his own and will eat up cap space that they need.