It comes down to how you ride. Even though gravel bikes seem to be the "thing", and your thing may not see much action with gravel type riding.
Also, your current situation with bikes. Perhaps the existing bike may still work for another purpose. That means you really have two bikes.
Since you already focused on these two Cervelo bikes, the preference would be R5, unless you have compelling reason(s) for the Caledonia.
If you're an older rider, I would look to see what the original Cervelo designer and co-owner is doing...Gerard Vroomen. Similar with deep pockets and perhaps better thought process.
Of the two Cervelo guys - Vroomen & White, its Vroomen who is still actively at it in an entrepreneurial way.
https://opencycle.com/mind