Time for some closure with Part 6. Based on discussions in the comments and offline chats during the Hackaservo.io tangent, I decided to button the servo back up with its stock ~9k resistor. I realized that while I'm getting more comfortable working with surface mount stuff, I'm not well equipped to rework 0402-sized components on a densely populated board; I'm not saying it's a miracle that I was able to replace the resistor, but I'm going to hold off on opening that servo up again for awhile as it's back to working in its factory state. We'll see if I have issues with loop tuning down the road; if so, I have a much better idea of which resistors to change.