How worried should I be about FOC in my arrows for accuracy? Should I be using extra heavy inserts and/or heads to offset the extra weight of lighted nocks and wraps on the back end? What is an optimal FOC balance point to try for?

FOC and arrow weight are certainly things you should know about, but I wouldn't lose any sleep over agonizing about them.  Just about any arrow/broadhead combo is going to get the job done if you put it in the right spot.  But to answer your question, I like my total arrow weight somewhere between 425 and 500 grains, and my FOC somewhere between 7-10%.  I feel like this is provides plenty of penetration potential while not weighing my arrow down too much.  I use 50-75 grain brass inserts in most of my arrow setups.