We just returned from Southern Spain. 4 nights Sevilla (would have been happy with more time, for sure), 3 nights Granada, 1 night Cordoba (consider a day trip from Sevilla by train if you get antsy, or one night stopover on your way to Madrid since the train goes through there anyway), 1 night Madrid before flight home.
Do the orientation tour with Concepcion (recommended in Rick’s book), for lots of ideas on other spots to visit while there. If you haven’t been to the Alcazar, we loved the gardens. The rooftop tour of the cathedral was fascinating with amazing views. And we loved the cooking class in Triana recommended in Rick’s book. We did a ton, but I would still consider going back to Sevilla just to be able to revisit, go deeper, etc. We did a tapas tour with Shawn, also from Rick’s book, and it was excellent and we left with recommendations for other places, so do it early in your stay. We were just starting to feel settled in when it was time to leave.
We stayed in an apartment as we were there with our son and it was our longest stay. More room helps us when we stay in one place for longer, as does ability to do a little cooking, etc. The place was great, but if you don’t need more space, won’t be useful for you.