Alex Smith and Dashon Goldson get most of the attention when discussing 49ers free agents, but Isaac Sopoaga and Ricky Jean Francois bring their own question marks. Sopoaga spent the season as the 49ers starting nose tackle, while RJF was the primary backup along the line, splitting his time between defensive end, nose tackle and nickel defensive tackle.
In looking back at regular season snap counts, Sopoaga was on the field for 31% of the team's defensive snaps. RJF was on the field for 27% of snaps. RJF rotated between various roles, including starting in place of Justin Smith at the end of the regular season, while Sopoaga spent almost all of his time as the nose tackle in the base 3-4 defense.
It is entirely possible the 49ers bring both guys back in 2013, but given the relatively limited use of the base 3-4, it would seem to make more sense to work out a rotation of RJF and Ian Williams at nose tackle, let Sopoaga walk and work to beef up defensive end depth in the Draft.
Of course, much of this depends on how exactly they feel about RJF and Williams, as well as Sopoaga to a lesser extent. We should get a good idea of this sometime between now and the first part of free agency. The 49ers might be inclined to just wait out either RJF or Ice depending on how the defensive line market plays out. We've seen the 49ers show every inclination to wait out their free agents and bring them back when the market does not materialize. I do think a market is out there for RJF, but Harbaalke has proven me wrong plenty of times over the last two years.