I see no travel time in your itineraries. For example, in Plan 2 you say:
1 day Ronda
No, that will be a half-day in Ronda if you are travelling from Seville that morning. The same principle applies to Granada and Córdoba, so your "1 day Cordoba" will just be a half-day in Córdoba.
Just remember, the journey time on the bus or train is only part of the overall journey time. You still have to travel between the stations and your accommodation at either end.
Plan 1 seems too busy, with plan two i think i will not see enough of landscape, nature etc
I agree that Plan 1 is impossibly busy. However, if you want to see more nature, you will need to cut out a lot of destinations. That is unless you count staring out of a window as "seeing nature".
28th Jerez,Cadiz,Gibraltar sleep between Gibraltar and Ronda
What do you intend to see and do in Jerez, Cádiz and Gibraltar?
some advice with nice hostel in Seville up to 50€ for two persons
If you are going to stay in hotels, forget all about renting a car. The daily rental cost plus parking will make the cost of the night in a hostel seem insignificant.