Traveling Europe from Granada

Shira, if you go to the Railpasses tab above, you will find a link to Rick Steves' guide to railpasses. All the information you could possibly need is there to help you evaluate whether a pass would be a good deal in your case. It's going to depend on how often you will be traveling and where, as well as the cost of point-to-point tickets.

It's an 'only you can do the maths' answer.

From Granada, it's a long train ride to almost anywhere. Certainly, of the places on your list, I'd only take the train to Sevilla (definitely) and Barcelona (maybe). For all the others, I'd fly. Athens would take most of two days each way by land and sea from Sevilla, so I wouldn't even consider any other way but flying. Many of the other routes would still involve overnight trains. Rick Steves is a fan of these, but many others are not. If you don't get good sleep on them (many don't), you arrive very tired and don't have a good time. Remember the pass doesn't include sleeper accommodations and doesn't include reservations (required for high speed trains in France, which you'll need to transit to get to many of your destinations). Look at train routes and schedules (but not prices) on The Bahn website. Put in a date next week, Sevilla as your starting point, and your intended destination. See how long it will actually take to get where you want to go. You can look at Skyscanner for flights.

I'd skip the railpass. It's cheaper to bus around Spain and take a low cost flight from Granada to other parts of Europe when you have a chance. Spain has high speed trains that work well for Seville and Cordova. Outside of those a bus trip will be the same or quicker to Madrid, Barcelona, Valencia, and coastal towns.