What kind of travelers are you? Do you prefer slow travel? or fast travel? Do you like to have time for seeing the sites but also for walking and exploring and lingering over drinks at a cafe? And enjoying the ambiance.
You do not have enough nights in Lisbon. If you are arriving from North America, you will have jet lag the day you arrive. If you go to Sintra for a day (which is lovely) you essentially have 1.5 days in Lisbon, which is not nearly enough. Lisbon has some wonderful sites and is a very interesting city for walking and exploring. There are great things to see in Belem, too, such as the Monastery, Discoveries Monument, Belem Tower and Coach Museum. For comparison purposes, we spent 5 nights in Lisbon, including a day trip to Sintra, and I wish we had an extra night.
Have not visited the Algarve so can't comment.
Two nights in Seville is not nearly enough. We spent 4 nights there and wished we had an extra night. There are many important historical and cultural sites in Seville. It is also a beautiful city for wandering with lovely plazas, fountains, parks, neighborhoods, etc. I would omit Ronda and spend that night in Seville.
Instead of 3 nights in Granada, I would spend 2 nights in Granada and 1 night in Cordoba. It would be a shame to go to Andalusia and miss Cordoba. The Mezquita is amazing, but Cordoba has other interesting and important sites, too. And Cordoba's charm is in the evening when the daytrippers have left and the city is illuminated.
If you want to see Toledo as a day trip from Madrid, then definitely spend 4 nights in Madrid. Do you like art? Madrid has some outstanding art museums, the Royal Palace, Retiro Park, and other sites. Some people don't care for Madrid, but we really enjoyed it.
So a possible itinerary could be:
Lisbon - 4 nights
Algarve - 3 nights
Seville - 3 nights
Granada - 2 nights
Cordoba - 1 night
Madrid - 4 nights
For a total of 17 nights on the ground.