I liked your point #8: know your limitations, know your niche. As you put it, in grad school you are surrounded by many brilliant people, and that can be a double-edge sword: you may be stimulated to grow intellectually, or you may feel as if you don’t fit. Finding your niche is the key to success, not only in grad school, but after graduation too. To succeed in academia you need to find what sets you apart from the rest, or else you’ll dissolve among the yearly mass of newly graduated PhDs.

I’ll add one more point to your list: once you’ve made the decision to get a PhD, don’t fall into “the grass is always greener somewhere else” mood. You will see job offers passing in front of you, often when you are at the lowest in your program, but you’ve got to stick with your decision and finish. It is the endurance component of grad school, and I’d say it is also number one key to success at a PhD.