Southern Spain Route

A simple travel route would be a 2hr train from Madrid to Córdoba, then a 1 hr train cordoba to Seville. Then a two hour train from Seville to Malaga. Day trips via bus from Malaga to Gibraltar and Rhonda, train from Malaga to Granada. Could fly Málaga to Mallorca. You could spend a week in Seville and a week in Malaga, and 2-3 days in each of Cordoba and Granada all depending on your interests.

Bus is also an option between Malaga and Granada. Travel time is about the same as by train, I believe, and considering both modes of transportation will give you more options for departure time.

I wouldn't spend time going to Tangier. It's not one of Morocco's best destinations. You can fly to very interesting Moroccan cities like Fes and Marrakech from a number of origins in Europe; you don't have to settle for a slog of a trip to Tangier just because you're in southern Spain this year.

A quick look at Skyscanner.com indicates there are non-stop flights to Palma from quite a lot of mainland cities, including Bilbao, Granada and Seville as well as Malaga and the expected Barcelona and Madrid. You won't have to travel round trip to Palma, so you can use it to connect two of your mainland cities. Flight availability and frequency may be quite seasonal, though, and I don't know when you plan to take your trip.

I think the biggest issue I see is that you are not spending any time in the area between Girona and San Sebastian, aka Northern Aragon which encomapesses the Pyrenees moutains. This part of Spain is immensely underrated and undertouristed, from the excellent hiking in multiple National parks, crystal-clear alpine lakes, numerous castles, monasteries, and fortified medieval towns. I'd first spend several nights here than Gibraltar and Tangier, which are tourist traps. Since you will already have a car, it makes all the more sense.

Here are some resources about the area:
https://theculturetrip.com/europe/spain/articles/the-top-10-things-to-see-and-do-in-the-aragonese-pyrenees/

https://theculturetrip.com/europe/spain/articles/11-reasons-why-you-should-visit-the-aragonese-pyrenees-at-least-once-in-your-lifetime/

Thanks for all the information. I'm still on the fence about Gibraltar and Tangier but it's on my husband's wish list. I did add 4 days/nights in the Aragon area, specifically Alquezar, Jack, and Lanuza.