CPS is a shadow of what it used to be after then farmed the chargers back to the local councils to look after. Its the only network I'd 100% recommend an RFID for as well, as half of them end up not having a signal to phone home and start charges via the app etc. Was great in 2019/20, £20 bought you an RFID card and you got free electricity for 95% of the rapids, now I wouldn't trust them to even work, Scotland went backwards unfortunately.
As for your 3-pin dilemma, do you need to totally fill the battery - what range do you get on say 10%? Also it is quite amazing just how quickly you realise the car sits around doing SFA for 99% of it's life.
I'll get a CPS RFID, I'm having a little moan as it's something I wasn't aware I needed.
You're right about the granny charger, it saves loads of money and the car is just sat there after all. It's getting the mindset away from "oh noes, I only have xx amount of range".