Thanks for the advice Tilt and Kare, I'll focus on Pali if I go to Santa Barbara and learn Sanskrit later in life if I feel compelled to do so.
A wise decision. Pali is more useful if you are interested in Theravada. On the other hand, if you get an opportunity later to study Sanskrit, just grab it. When you have a firm basis of Pali, a knowledge of Sanskrit gives a better understanding both of Pali and of the dialect continuum in India at the time of the Buddha.
When I studied Sanskrit, I already had a fair knowledge of Pali. My initial feelings were that Sanskrit is so "unnecessarily" more complex than Pali, both in grammar and in the rigid sandhi-system. But as I got more familiar with that language, and as I worked my way (with lots of help from my teacher) through poems by Kalidasa, I came to realize and appreciate the special kind of beauty in Sanskrit poetry. Or maybe I appreciated that beauty the more just because it had taken quite a lot of work to get access to it.
Wishing you the best of luck in your studies!