If CZA had proven play calling experience, I think he would definitely be the first choice. However, CBJ needs to bring in solid, experienced OC with experience in the uptempo, spread offense CBJ uses. That's why CBJ's connections going back to Rich Rod will play into the choice. I would bet that Rich Rod and CBJ have already talked. Also CBJ is always well prepared, and I'm sure he has a notebook of resumes ready for just such a situation.
For openers, Rod Smith and Calvin McGee make good sense as strong options. There are others, and we will just need to wait and see. I expect CBJ to select his OC within 2-3 days. The only question will be if the new OC wants to bring some staff with him. That could shake things up some.