Chris Maxwell,
That's not how I see time, in fact, I see anyone who sees time in the way you described; "based on the orbit of our planet around a star", as a bit silly. I believe in Newton's time where there are no regions where time is different. I also do not think time and space are in any way linked. The fact that light bends or slows down at certain points in the universe has nothing to do with time, it's to do with gravity and photons.