I think that would be a great route to take back. We left the San Blas for Providencia/Hobbies/Roatan and had a good sail - the Caymans are pretty much along that route.
We left Colon for the Windward
Passage and were very hard on the wind. We could have easily sailed to the Caymans on a close reach from there.
Leaving from Cartagena would be even better because not only would you have a better wind angle, but you will likely have a west-flowing
current in your favor much of the way. Leaving from
Panama has you against the current more.
Keep in mind that generally in spring/summer the winds are NE close to the Panama/Colombian coasts, but change to E somewhere around 13* latitude. That helps even more.
Mark