The bride and I just bought ourselves e-bikes. I have severe arthritis in my lower back, L1 through L3, and to make it a step worse, because of my height, I have an extra vertebra in my back to add to the misery. I have resorted to a spinal pain block implant, which blocks 80% of the pain 90% of the time. Bike riding or any activity helps with arthritis, but hard peddling hurts, so I traded in my manual bike for an e-bike.
The criteria I used to choose were affordability, ease of transport, step-through, a reputable brand, good customer support, and dirt road handling (I live far from paved roads). After a winter of looking and watching videos, I decided on Lectric XP 3.0s. They fold in half and fit inside a 40/50 gallon tote. They seemed to be a fan favorite, very popular with the RVers, have good handling characteristics on dirt roads, and have a good range, way more than we need for a day out.
My bike suffered a minor trauma in shipping. The derailleur was working, but it wasn't selecting all the gears and would skip gears. I knew absolutely nothing about a derailleur; I didn't even know what it was called. So, I sent Lectric an email about the issue. They replied, and on a Sunday, with detailed instructions and a video link on how to align and adjust the derailleur. The information was so good and so complete, I had it operational in 30 minutes. That is the kind of support I look for, and they delivered.
There is no shortage of eBike brands, and that makes it hard to make a decision.