I've been trying to figure out what I'd do for some time (assuming he opts out).
1. Extend CC. I just don't see them doing that. They have Lewis and Lee ready by middle of next year, and they can sign a legit player at another position for less. (who/what position, unsure).
2. The real question, imo, is the timeline for Lewis' return.
If he's projected back "early", I'm ok with Palacios/Gordon as placeholders. Early is May 1 or earlier.
If he's projected back later than that, I try to sign a SS. Maybe even one of the expensive ones. I don't see THAT happening, but it is possible. I haven't checked the non-expensive list yet.