For long-distance trips, I am using A Better Route Planner, warmly recommended. Tells you when to stop where to charge how much, considers elevation, weather, wind... Only issue is that with default settings it is terribly pessimistic about the I-Pace's consumption in my experience.
In cold weather you really want to head of with 100% SoC and battery preconditioned. That way the first charge will be fast, and every stop after that as well because of fast charging the battery will be nice and warm anyway. With a warm enough battery you should see 95-105kW up to 40%, gradually dropping to 70kW at 60%, 50kW at 80%, 35 at 90, 15 near 100%.
Very odd, all the negatives about Electrify America. They are the equivalent of Ionity in Europe, I understand, and Ionity is certainly the go-to provider in my experience. For €200 per year the rates are roughly the same as at home, they are very reliable and if not, you can call and get real support 24/7.
If you do not get what you expected, please pick up the phone and call support to report the issue. Support teams can simply reset the charger remotely, you may be doing yourself a favour as well as all coming after you.