Apart from reducing the power used by the AC System, ECO has no real advantage over any of the other modes. It is your right foot that determines your range.
I would sort of agree with you but ECO restricts power to the motor and that in a way controls the lead in your right foot!
I came back from North Wales, more or less Anglesey, via Shrewsbury and Kidderminster to the M5 and the GoM made out that we could have got to Portsmouth.
We might have been able to do that had we not gone on the M5 and up Birdlip hill which rather put the mockers on achieving that!
Whatever way you look at it the ZS EV is a very economical car, we were touching 4.3ml/Kwh up to that point.
Cross country, up and down A and B roads keeping to a max of 60mph and below, I don't think that was bad. We weren't tootling along either.
On my car ECO completely disables Air Con, it says reduced but the air coming out of the vents was exactly the same as the outside temperature.
It was ideal EV weather, the battery was nice and warm.
Driving style has a big influence of battery consumption. Accelerate away from every corner or traffic light and you won't do very well! Imagine an egg on the bonnet not rolling off!!
I personally found that cruise control is not the most economical way of driving as I can control the pace rather than keep the car at a constant(ish) speed.
Everybody will have their own way of getting the most range out of the car.
If I have to use a motorway I find a nice lorry with lots of reading matter on its rear and stick behind that!
It is funny how you find a Tesla or other EV behind you as well!!
When I had the I-Pace I was on the M4 on a Friday in the company of another I-Pace driving as usual behind an artic. When we approached Bristol we got stuck in the normal Friday traffic jam and pulled up alongside each other and had a chat across the lane! to admire each others car, his was the elegant grey, mine Caesium Blue. We compared consumption and worked out we were only 4 cars behind an Audi Q5 that had shot past us some miles back doing probably the legal limit and a bit more.
We could sit there and chat not using any power whilst the A5 was still consuming diesel inching forward in the jam.
Viva the EV!