We were planning to go to Nebraska, and specifically to the road (state route 92) that runs through Tryon and hews closely to the centerline, but a deteriorating forecast for that area caused us to make the trek to Unity, Oregon. I am glad to see that the weather was fine in Nebraska (as it was where we were.)
Our reasons for picking both areas were: 1) statistically, a high probability of clear skies in the morning at this time of year; 2) a clear view of the sky (checked using Street View); 3) roads running along the centerline of totality, so we could hope to dodge clouds if we had to; 4) somewhere likely to have a low density of viewers, so that it would be possible to move, if necessary, without being caught in traffic. When switching to Oregon, we also considered wildfire locations and forecast wind direction (the forest service has frequently-updated fire location maps and reports.)
We printed maps showing roads and the path of totality, in case cellphone navigation failed us (which it did, but on account of the location's remoteness, not service overload.)
We were least certain about the density of viewers, but the roads were so empty as we approached our destination that I worried that I had made a huge navigation error!