We didn't finish our Camino Mozárabe last year, and we walked only to Castro del Río.
We spent extra time in the following towns:
Almería, Guadix, Granada (we had been there before walking the Camino), Alcalá la Real, Baena.
As we also walked the Jaén branch, we spent extra time in Jaén, which I highly recommend.
We're going back to the Camino Mozárabe in April, and we have planned to spend extra time in Córdoba, Medellín and Mérida.
We intend to walk the Málaga branch, so we're also, as you noted, spending extra time in Antequera.
¡Buen Camino!