Mandarin or Japanese a long shot. I'm afraid I would find the eastern languages a little more difficult to learn and would lose interest. For me, Spanish was easier than Japanese, plus you can already read it. I knew how illiterate people feel when I was in Japan and had no idea what 90% of signs said. Japanese is pretty nice and logical, though, without so many weird conditional rules that we have. In most parts of the country, you'll have the most opportunities to hear and practice Spanish, which is very important. Were it not for the lady friend, I never even would've attempted Japanese, as there'd be no use for it, which means no real practice, which means no retention.