Looking over the starting percentages for thief skills, I always think Pick Pocket is way too low. It was often the first skill young thieves would learn. I think it should start around 50%, especially when you take in the percentage loss caused by higher level targets. Having it start around 30% means that the majority of cutpurses would be caught on their first day, which is just silly. Unless you like a city with a bunch of missing their right hand.
I also think some of the other skills start too high, especially climb walls. Most thieves weren't second story men. Open Locks, Climb Walls, and Find Traps should all start low and only really start increasing once the Thief gets to mid level. Not sure how I'd address this in game, unless I port in a version of the 2e thief skills table (which I love, and I'm glad it's in the BFRPG Appendix).