Actually, I'd recommend installing the myChevrolet app on your phone and using the “Energy Assist” feature in association with CarPlay/Android Auto.
It will tell you what your estimated battery percent will be at your destination which can alleviate anxiety, especially as compared with watching the trend bar. With the trend bar, if you go up a hill, the car will think the worst imagining the hill goes on forever, whereas the app, which knows you'll be heading down the other side, won't be worried.
I have found the Energy Assist app to be very quirky. In fact, right now it is plotting my vehicle in the South Atlantic Ocean off the coast of Africa. Obviously not a big help when it plots my vehicle in the wrong place. However, I will try it the next time I travel per your suggestion, or at least practice using it.
I still believe the trend bar has valuable info to use. No, not the short term ups and downs over hills. In fact, a shorter yellow downward trend bar (generally 1/2 way or less) is usually no problem at all if you have a built in buffer or are closing in on your destination. Yes, you are eating more range than miles, but at a slow enough pace to manage. When the downward trend bar extends 3/4 to all the way down, range is going down at a much quicker pace than the miles to stop/destination. At this point, an adjustment will likely be needed soon to speed to reign it back in, especially if you are farther away from the stop/destination.
I found that starting off at 65 mph on the highway after my first stop worked really well. When the trend bar showed green, I increased my speed. Eventually, I was able to travel 70-75 mph with no issues as conditions (wind, elevation) improved. On the turnpike in OK, I traveled 75-78 mph with a generally short yellow downward trend bar...ie no issues.
By the way, I definitely agree that Android Auto using Google Maps is essential to use to assist with range management.