I find I save overall trip time by driving fast, and charging at low SOCs, over driving slower in order to meet some range goal.
I have to disagree on that one, as making that one stop really really really lowers (like, big time) your overall trip, average speed.
If I could make it to my destination driving 55mph without a charge stop, vs driving 90mph with a charge stop, I guarantee you driving 55mph with no stop will get there first,
Now if you tell me it's more fun driving 90mph (with a charge stop) vs. driving 55mph and no stop, then there is no argument there.
That 0mph time will really kill your average speed... and from the moment you exit the highway, it's all 0mph (not just the charging stop) as you're not making any trip progress.
Also it would be nearly impossible to maintain 90mph if there is any amount of traffic...
I once did an efficiency test, as I wanted to see my % and rated mi drop difference driving 10 miles at 55, 10 at 60, 10 at 65, 10 at 70, 10 at 75 and 10 at 80, all in AP...
I was on a long boring trip, late evening, no wind, no hills (I-95 in FL) temp was low 70s so climate off... and my car, (a 2016 75D with 40k mi at the time) achieved 1 to 1 rated miles around 60-65, more than 1-1 rated miles <60 and less than 1-1 >65
Bottom line, I wasn't able to maintain a constant 80mph due to traffic interfering (75mph was the most that could be kept consistent over 10mi)
So generally anything above 75mph would not be easy to maintain as an average speed over a long trip except for rural areas.