As far as out big 3 FA's go (Wagner, Williams, Juice), I think we could actually be okay if we lose all 3.
A replacement for Williams might already be on the team, and with the difference that a guy like Pierce is getting paid and what Williams will get, I'd be okay making the trade off (even thought he's been one of my favorite draft picks in recent years).
If we can't get Wagner at a reasonable price, we can bring someone like Zeitler for possibly less money and then change a couple of guys' roles on the OL.
And as much as I like Juice, his position is pretty easy to replace for us I feel (since we didn't really seem inclined to use him as extensively in the pass game as he could be used).
I think I'm echoing a lot of other people on the boards, and knowing our FO, this is probably the way they're looking at these guys; good, but replaceable.