Hi JDLaw.
That's some great advice. You've nailed so many key aspects of successful GMAT preparation.
I have one to add, one that may help you.
Do much of your practice UNTIMED and shoot for VERY high accuracy, as in close to 100% on easy, 90%+ on medium, and 85%+ on hard questions, and even better is to shoot for streaks of questions correct in a row. Then, once you achieve such accuracies and streaks, you can work on answering questions faster while maintaining high accuracy.
In doing what it takes to achieve very high accuracy and long streaks of correctly answered questions, you develop the skills you need to get questions correct, complete sections on time, and achieve your score goal.
For an in-depth discussion of how best to practice for the GMAT, see this post.
The Best GMAT Practice Methods