Mine actually makes a decent attempt to adjust to recent trips - which I understand, but is also kinda dumb. If the last few trips I've made were highway, then my GOM range goes down. After a few days of city, it goes back up. I think it should adjust to show you the range based on "If you kept driving as you have since you started this trip" (i.e. take the miles since last charging session and divide by the battery % used since the last charging - anytime after you've moved 5 miles or more.) That would be the sanest (and easiest) thing to do. If you keep doing what you've been doing today, this is how far you can go. And, if it knows WHERE you're going, it should tell you if you're not gonna make it (or make it HOME from there) without a charge.
It doesn't matter if, for the last month, I've only been driving to work & the store ... TODAY, I'm driving at 75 on the highway, uphill, and into the wind for the last 10 minutes, so ADJUST and tell me how far I can go if I keep doing what I'm doing!!!