I think it very much depends on what you want to do with it.
Languages are limited unless you have another skill to go with them and especially considering that there is a huge amount of competition from native Spanish speakers who probably speak English far better than Spanish is taught over here.
You should also consider whether you want to have the year abroad as part of your course as is standard with degrees which include languages.
I started off doing a degree in French, German and Italian after doing GCSE and A Level French, German and Spanish. I changed to law after the first year when it no longer became the challenge I wanted and I realised that I would still need another skill for most language jobs.
I went on to become a lawyer and as I didn't want to go into international law in the city, I can honestly say that the only language I've ever used is some sign language.
I would have had far more use with Indian languages, oriental languages or ones like polish.