Have you seen About Time? Some of the aspects of that movie seem to have explored some of these ideas. Except it's not scaled up to a society of time travelers, of course.
That's actually a pretty cool concept. Star Trek has hinted at the idea of massive use of time travel by a society a little, but of course, it's difficult to write if you want to keep internally consistent about paradox plot points.
Maybe there's a clean way to approach paradox issues (e.g. the universe course corrects), maybe it can be completely side-stepped, or maybe it can be swept under the rug.
Honestly, if technology is the reason for time travel, and if all information about NLT is available throughout the whole span of time that it exists, then it could very easily be something built into the technology that makes it possible in the first place. The tracker one wears would have a kind of paradox-avoidance feature that keeps one from going to a place/time they've already been, or from encountering any situation that would otherwise divide by zero.
"So, Bob, I was going to attend your son's first birthday party, but my paradox-avoidance ring went off. Apparently, your son had a dog that dug up a sapling. If I go to your son's party, you don't end up buying that exact dog for him, that sapling would end up growing into a tree that falls on my grandmother's house, somehow preventing my birth. Sorry about that, bud."
Perhaps it could work quietly in the background. The act of avoidance could be felt like an inconvenient detour. "Damn red light."
I recognize the cover art to the movie, but I've never seen it.
Wasn't that actress also in another time travel movie, The Time Traveler's Wife?
Great movie.
Oh, and to answer your question on "About Time", I have actually not seen that to my recollection, but it sounds like I might need to.