As an old hypermiler since the MY 2000 Honda Insight, I can tell you that a little technique will beat cruise for efficiency every time. For the best results at a given speed, you'd want to allow the car to lose speed going up hill and gain going down hill and when passing, very gently get back up to speed.
Hypermiling techniques can be irritating to other drivers in heavy traffic and EVs are more efficient in accelerating so I don't worry about it much these days, but I have seen marginal improvements in range by using my right foot as opposed to cruise. Also, at highway speeds Eco seems to accelerate more gently than other modes in cruise, so I have been using that as my default.
As for one pedal vs. low regen, I'm firmly in the low regen camp as preserving momentum has been deeply ingrained in my driving style and it's easier to do that with the traditional two pedal set up. Also, my wife drives the I Pace whenever she can, and I don't need to worry about her learning curve with low regen.