Do't know which battery (there are several) / how many motors you have, but the basic mpkWh over which one has control are
tire inflation pressure (do it manually) ,
speed,
how smoothly you accelerate. Use Adaptive Cruse.
elevation change (going uphill).
The cold (and heat) and wind are not under our control. Cold can really cut into your mileage. A lot.
It sounds though, as you are doing just fine. I calculate I have about 300 miles of useful range ( using 80% to 20% recommended SOC of a 500 mi EPA estimate ). On a trip I charge-up past ninety percent at home to give me a comfortable margin. No way I can drive 300 miles without stopping, so no worries. I've done the trip from my home charger (philly 'burbs) to the EA charger bank in Seabrook, NH and it's one full charge on the GT with a few electrons left over . It's scary to arrive with below 10%, but the pay-off is seeing the 350 chargers live up to the promise.
I learned a lot about how to drive an EV on long trips from watching the
Looks like you need to "map out" the chargers ahead of you and sip from them where the charging is fast, (never top-off) then leave for the next one. This is what I do now.