Price is all you can think off?
Example's would be paypal support, monthly bills, annual bills, dedicated phone app, dedicated windows app, energy advisor service, energy saving products, energy monitoring products, and more, these are the first things that popped up in my head as was typing this reply. There is more but the list would just go on and on.
I can see where you are coming from but the issue with those payment ideas is that In reality the vast majority of the market want a fixed monthly payment that they don’t want to think about.
It’s the reason people flocked to direct debit in the first place, that and to avoid the extra charges of not doing so.
Many suppliers support actual useage billing but they charge you more for the privilege because it costs them more to administer. To support PayPal, they’d have to charge even more due to the fees. Why would you pay extra to pay my PayPal over direct debit?
Pretty much everyone has an App. Having or not having an app doesn’t really add value. Most people switch via a price comparison siites and are the main route of descoverability for energy suppliers. Most meters read themselves and websites are optimised for mobile either way.
All the big suppliers offer energy saving products, advice and monitoring and have done for years so that isn’t anything new either. Likewise they would have a cost which most people just don’t want to bear the burden of that.
Like I said, outside of price, it’s very difficult to differentiate yourself in the energy market.
Let’s be honest, you just aren’t going to move from a behemoth like British Gas to a little fledgling company unless it was cheaper.
Yet Octopus do just that, they have made the market a different place for a lot of folks, through the use of smart metering that is being rolled out. I'm sure once you order your Model 3 you'll be looking at them as a supplier.
Octopus are an interesting supplier, there not one of the big boys but they aren’t exactly small. Outside of agile, the Ocotpus offering isn’t particularly unique anymore.
Go wasn’t exactly revolutionary, it’s just a variation on economy 7. I’d argue that thing that made attractive was ultimately the price though. You wouldn’t have signed up to it if it was more expensive.
It’s exactly what was initially attractive about agile in a falling market with low demand, it was very cheap. As soon as that changed everyone ditched it so it falls back to a price motivation again.
P.S. I’ve ordered one

. I may end up with Octopus, I may not. It depends who can deliver the electric the cheapest and lots of places offer similar options but the market is a bit of a mess at the moment.