I've waffled on signing William's. I certainly would not be down on the signing.
But the franchise, I believe, is wanting to build through the draft. If this is the case, then you have to trust your decisions of draft picks. Signing William's invalidates the signing of Rankin, who was picked to play on the left side either tackle or guard, with guard seemingly his best fit.
The way our recent drafts have gone, our OL should be: Howard, Rankin, Fulton, Scharping, Henderson.
Unless you think Rankin can move over to the right to challenge Henderson, signing Williams goes against your draft strategy and delegats a high draft pick to a backup role.
To sign William's, it will probably take next year's 1. This is too high a cost. The most I go is our 2, but I think the team should stick with the OL we have and invest next year's 1 or 2 on a RT, if Henderson doesn't work out.