Saw several lights, doing various things like strobing, moving, disappearing after one slow flash, splitting, and a swoop.

While driving west along Hwy 20 in Central Oregon about 9pm on the evening of September 24, 2015, I noticed two yellowish/orange lights traveling parallel to each other and to me, and also in the same direction.  They seemed fairly low, and I assumed they were the lights of a low-flying small aircraft.  (A few minutes and miles before, I had passed an accident just east of Sage Hen Rest Area, and I thought perhaps an airplane was involved with rescue, though now that makes no sense to me.)  I continued driving, forgetting about the lights for a short while…a minute, perhaps two.  When I looked again I could not see them even though I would have expected to still see an airplane.  I thought they might have been lights that reflected in my car, how sometimes the headlights of another car can reflect in strange places inside your own vehicle.  But traffic was very sparse and there were no street lights or such.
Within a couple of minutes I again saw lights in the sky, maybe ten or twelve scattered within a span of about 40 degrees to the left and front of my vehicle.  My recollection of detail is not good, but I recall them going in different directions, mostly slowly.  Some blinked slowly a few times, some came on only once.  One split.  They disappeared altogether and then came back about 2 times before I pulled over.  Nothing appeared in the five or so minutes that I waited, so I continued driving.
They appeared one more time, however.  Again there were a dozen or so moving about.  The last thing I was able to see was one of the lights dropping vertically and then back up to the right (northwest) in a curve in the shape of a barbless fish hook.  It blinked during the dive about 8 or 10 times, and I think the previous light would still be fading out of its glow when the next flashed on.
This occurred over a distance of about 10 or 15 miles and 15 to 20 minutes.  I think I was between Riley and Hampton, Oregon.  It pretty remote and the south side of the highway appears like unoccupied land.   I was not able to determine the actual altitude and size of the lights.  They were about 30 to 40 degrees above horizon, and were always between my left and straight ahead.  Perhaps they were other places too but I did not see them.
After eliminating airplane and reflection, I considered perhaps hot-air balloons because during the second round of sightings they were initially lighting up slowly and fading out like I imagine the propane flame on a balloon would do.  But their antics eliminated that option in my mind.  Remote controlled flying craft are—to my knowledge—fairly small and these were in a large area.  I do not know enough about drone devices to take a guess if the lights could have been something like that.
Please note that my estimates of distance and time are approximate.  I did not think at the time to pay close attention to such detail.