In 2010 we drove some of the itinerary you are planning. Here's my trip report for that portion.http://www.fodors.com/community/europe/spain-trip-report-part-2-sevilla-ronda-nerja.cfm

Cordoba can be done in an afternoon. We took the train from Madrid to Sevilla. It stops in Cordoba around noon. We stored the luggage at the bus depot across the street, got a cab up to the mezquita, had lunch and saw the sights. Bus back to the bus depot, got the luggage and then got the train to Sevilla.
We did Toledo on a day trip out of Madrid, and drove to Granada after leaving Nerja.

I recommend a night in Rhonda. It was enchanting, and really nice after all the tour busses from the coast clear out. Your route from shown between Rhonda and Sevilla is the track we took. Zahara is a neat little village. Nice hotel there. Also, you will pass that old castle enroute.
After Ronda, we drove to Nerja, east of Malaga. After two days there, we drove up to Granada.
Enjoy. We had no problems driving in Spain. The roads are generally good. Big cities can be troublesome, but that's true anywhere when you are unfamiliar with the streets. Just follow signs to the highway numbers and towns. We did not have a gps unit, but very good Michelin maps.

Ubeda makes a great stop for lunch if you have time. With 4 nights in Sevilla you should have time for one daytrip - which I'd definately make cordoba. I'd visit Ronda en route from Granada to Sevilla. I do have to wonder why you're not dropping the car on arrival in Sevilla. You won't need it once you arrive and if you want to daytrip to cordoba the train is easy and fast - also a great experience. I can't imagine the additional rental cost for 4 days, parking and gas would be less than the train tickets. And that's the only time you'd even have to use it with the limited time in Sevilla.

We and another couple were in Spain in April 2012 for 3 wks-- only portion we drove was from Seville to Granada then down to Marbella on the Costa del Sol. I agree, no car needed while in Seville. Do not miss Cordoba, the old town is just lovely to roam. We stayed overnight, en route to Seville, via train from Madrid. Upon leaving Seville, we drove to Jerez overnight but didn't love it, wish we had gone further to Cadiz on the west coast. We were not in Jerez the day to see the famed horses. That said, as we continued east, we stopped for lunch in Arcos which we liked alot, stayed in Ronda for 2 nts, which we loved. Driving in Granada was a challenge as much was under construction. GPS does not help terribly when your hotel is in a pedestrian zone! And don't miss the Metropol Parasol in Seville (which, somehow, we did!).

Reason I'm not dropping it off immediately is the rental cost for 7 days was exactly the same as it was for 4-5 days; 7 days seems to be the sweet spot for the daily rate. So I kept it for that length for flexibility. But we may well return it earlier given, as you say, we also need to pay for parking (when we essentially won't be using it, unless we do use it to get to Cordoba).

So while we have it (at least until we get to Sevilla), we'd like to maximise the use of it. A visit to Ronda sounds like a good idea, although unfortunately a night stay is not on the cards (we have booked our Sevilla accommodation, plus we don't want to do another one-nighter somewhere).

Thanks Bill/Cathy!

You might want to check out this restaurant on your way to Seville.

http://www.restauranteplazadetoros.com/en/presentation.php

We took the opposite route, and wandered north from Seville through the white washed villages and came to this charming town. We managed to find this restaurant, which was part of the local bull ring.

My wife loved the place, and I thought it was great also.

BillJ, thanks for the link to your report. It's very thorough and a great read. Sounds like you both had a fantastic time

Rastaguytoday, thanks for the link to the restaurant. Will see how that fits in - we might be past there too early unfortunately for lunch.

Also, thanks aliced

Thanks all for your feedback so far. Based on more research this is our updated drive/route: http://goo.gl/maps/R3p95

Drive day 1: Madrid -> Toledo; stay overnight
Drive day 2: Toledo -> Consuegra -> Almagro -> Úbeda -> Granada (stay two nights)
Drive day 3: Granada -> Priego de Córdoba -> Cabra -> Córdoba -> Sevilla (with a good 3-4 hours spent at Cordoba before heading onto Sevilla); stay at Seville four nights

Drive day 4: Sevilla -> Zahara -> Grazalema -> Ronda; then returning to Sevilla (not via the mountains).

Drive day 4 will happen at some stage during our Seville stay, perhaps. We have three full days in Seville, so this would be one of those days if we elect to do it.

Any final critiques most welcome

Forgot to add, I think I'll probably drop Almagro - not sure whether it is worthwhile passing through?

It's videos like this that make me want to do day four: http://www.youtube.com/watch?v=6AcMAjcrXJk

We were in southern Spain last spring and really enjoyed the trip. We stayed a couple of nights in Ubeda at the Parador and I would certainly recommend visiting the town even if you just stop on the way. The nearby town of Baeza is also very lovely. The pictures on our blog might give you an idea of what to expect. There are also posts on tapas in Sevilla and the hotels we stayed in which could be interesting too.

I don't think that you're not going to want to keep the car in Seville, so I presume you'll return it and then rent another one if you decide on the day trip "drive day 4"?

http://somuchmoretosee.blogspot.fr/2012/12/ubeda-jaen-spain.html

We will probably keep it - as it was cheaper (or the same cost) to rent it for 7 days than for four or five; and certainly to then go and rent another.

We'll probably just park it and return it after our day four sojourn.

I will have a look at your blog, thanks

While in Ronda,you shouldn't miss Setenil de las Bodegas-a town famous for its dwellings built into rock overhangs above the Rio Trejo. It is only 19 km away from Ronda.It took us 45 min to go there by bus but you have a car so it will take only 25-30 min.
http://www.google.com.tr/search?q=setenil+de+las+bodegas&hl=tr&tbm=isch&tbo=u&source=univ&sa=X&ei=yR47UcrAMYS47AaP54CACg&sqi=2&ved=0CCsQsAQ&biw=1366&bih=640

Wow, that place looks incredible. Will add that to the return voyage back to Seville - thanks for the tip!

We had a wonderful dinner at this restaurant in Seville and the cost was so reasonable. It's a don't miss. vineriasantelmo.com

I don't think you'll have time for drive #4. Yu have 4 nights in Sevilla but won't arrive until late on the first day. So basically you have 3 days. Sevilla really needs 3 days itself as you will likely discover.

For drive #3 I wouldn't anticipate staying for very long in Priego or Cabra as it will already be a full day driving from Granada to cordoba, sightseeing in cordoba and then driving on to Sevilla.

Thanks iris, I've added that to my research list!

Cathy, I totally agree with your point. Consequently, I wonder whether it would be better to drive Granada --> Ronda, then onto Seville via Grazalema --> Zahara, and then possibly do Cordoba as a 1/2 day trip, or miss it altogether?

If only we had one more day; alas, that is the opportunity cost of holidays.

I think you're going to have to decide between Ronda and Cordoba or sacrificing a day in Sevilla. Driving and exploring from Granada to Sevilla will have you arriving in Sevilla late on day 1. This will give you 3 full,days for Sevilla. I doubt you'll have time to do a daytrip to cordoba with only 3 days in Sevilla - unless you take time from Sevilla. For Granada to Sevilla I'd choose the one I most want to do in case once you arrive in Sevilla you're not able to pull yourself away.