I'm still uncertain about the operation of transistors, and online info hasn't completely cleared it up for me. I'm sure for my project I can just buy whatever, but I'd like to understand a little more. Is the base resistor to make sure I don't pull to much current from my RPi pin? Do I want to maximize the base current so that I can also maximize the collector current? Will that drop the voltage of B below C, thus preventing saturation? Thanks!

Thank you for providing answers to all my mistakes, even if those that ended up not mattering. I was confused as to when a transistor actually works and completely missed the obvious solution...