I like those ideas. The bus trip from Malaga and the staying at the Ronda's parador are excellent choices. We did the same thing ten years ago. Then we bought a house in Ronda and the rest is history. Another way to go is a Malaga train trip to Ronda and staying in Ronda's old quarter. I recommend the Hotel San Gabriel.
On the car trip the second day, think about following the road signs to Seville, maybe visit the Roman ruins at Acinipo (10K from Ronda), then touch towns like Sentinil (12K), Zahara (15K), even Grazelema (30K), There are several fine parks in that area. Lots of good hiking and cycling. The area guides are inexpensive and worth the expense and piece of mind. We take our family horseback riding during the summer holidays.
For more travel ideas, check out theolivepress.es.
It's our local english paper for southern Spain. Good luck.