I was able to solve our speed issue by turning off the Object Manager while using PA30 (settings -> hide object manager). I'm guessing this object manager somehow caches employee records, which is why it was affecting the speed so much. With the object manager hidden, my script is now running in less than 5 seconds, whereas it was taking around 30 seconds before.
Just FYI for anyone who is working with PA20/30! I wonder if there is a way to push this setting out to all PA30 users??
~ Cheryl