Thanks for all your feedback. Gibraltar sounds like it would definitely be a worthwhile trip. I wonder why some of the people on the tours didn't like it. Must be just a matter of taste.
Bob/Mick, it's interesting that neither of you enjoyed Alhambra. I've seen it crop up quite a few times on those '50 things to see before you die' lists so would expect it to be quite spectacular.
Jaya, I totally agree with your attitude of seeing/experiencing as much as possible while you have the chance so I might as well do all the excursions as I'll probably not get the chance to again 🙂