Strange question. I can't think of any reason you couldn't start learning any language right now. Don't say lack of time, because short lessons at a regular pace are the best way to learn anyway.
Right now I'm learning Irish. At some point I'd like to learn the other Celtic languages, primarily Welsh and Scottish, but I'll probably start lessons in Russian before that - if for no other reason than I inherited a Rosetta Stone for the language from my mother. I imagine Scottish will come quickly after learning Irish, given their close relationship. I'd like to continue learning French at some point. I took courses in it back in school, but after the courses ended, I dropped the language entirely. I never attained fluency, but I love how the language sounds and flows off the tongue. As someone mentioned earlier, Basque would be an extremely interesting language to learn also.