I'm not going be surprised if they sign Pears over Hairston because he's been healthier during his career. I am thinking a two year deal as a backup with incentives. He will have more time to work on his technique (he moved to guard late in the preseason last year) and hopefully get some better coaching. As you said, his age may cause that not to happen, but I won't be on here wailing about it.
To me it looks like Glenn, Williams, Wood, Urbik, Henderson with Kujo, Richardson and Pears/Hairston to start the offseason with.as the primary Oline. Not saying they won't add another guy or two, but since Whaley has had a hand in a lot of these guys it may be very similar in July.
I think Rivers and probably one of the te's will go, Wynn doesn't get resigned. I also think Boobie is at risk depending on how Roman views him from their time in sf. There was a reason Boobie left SF, and SF kept drafting guys so I assume Roman doesn't see much value in Boobie.
I really hope we will get to a point where we try to resign our own guys and not bring in many FA's, more like what Pittsburgh does. That means sticking with a coach and front office personnel longer to provide the stability to get guys signed to their second contract.