A relaxed weekend!
Valencia is a very beautiful city. Also definitely a big plus is that it is not as touristic as Madrid and Barcelona so it is much more relaxed there and you can just enjoy yourself. Just walk along the dried river bottom and visit the big beaches and I think you will see it too! Also you will not need public transportation (which is also not too good) since everything (except the orange fields) is in the centrum.
Insider Tip:Eat a lot of oranges - oh my god they are amazing there! A lot of shops and restaurants have siesta so you better get used to the spanish meal times.