Dunno about rates etc. but I have a couple of "general" suggests
If your driveway has parking for two cars assume you will have 2 EVs soon / at some point.
I have 2xEV and 2x Wall Chargers. The wall chargers are spaced apart where the cars normally park ... with hindsight I wish I had mounted them in-between where the two cars go, the cables are long enough to reach ... but where they currently are, towards the extremities of each car, I can't reach one-from-other. It would just "be easier", that's all, and avoid some of the car-shuffles we do
We also put in a Commando-socket in case the Wall Charger broke, or for a visitors. We've used it enough times in 7 years that I'm glad I did it. My first Wall Charger brunt out ... GrannyCharger and Commando-adapter was just as fast as the wall charger until Sparky fitted the replacement.
Whilst Sparky was at it we also installed an outdoor-socket - e.g. for car cleaning. Surprising the number of builders etc. we've had here who have needed electricity and, in olden days, would have had a window wide open for that ... in mid Winter!
If your driveway has room for two cars consider "making provision" for a second wall charger - if there is any infrastructure that is worth doing - e.g. run a second armoured cable, to save drilling the walls again!
I have a Tesla Charger (long, very robust, cable - but dumb) and Zappi (much thinner cable, but of decent length, ability to do "Spill excess PV to car") and actually its benefit for me has been limited ,,, might work well for most-people / most-circumstances.
I have PV and Battery. On a sunny summer's day if I'm going out this afternoon I will charge car (from PV + Battery) this morning, deliberately deplete the PowerWall, and let it refill later. In fact my PV generates 15kW max ... no point charging PowerWall to full and only then having Zappi charge the car, as that max's out at 7kW ... so what I actually need is a solution that will charge "everything" at the same time, to stop the PowerWall filling up first and then there being too much juice for Car Charging. All neatly handled with a bit of software, but in effect the Zappi's ability to "spill excess PV to car" has become redundant for me.
I like that my chargers are dumb. I don't want them to be clever and sort out what charging I want. I have 2 cars and 2 chargers. Depending on who comes home / when / what other visitors we have ... and where they might have chosen to park if one of our EVs wasn't on the drive when they arrived ... I just want the CAR to say it wants to charge. The Charger being dumb is just fine.
If I have excess solar I have a pecking order for which car should get it ... i.e. the one that is going to needed for a forthcoming long journey. For anyone with a "run around EV" that will be "the other one"
- but even then, once in a while, the run-around will need some Solar top-up - especially if the long-distance EV battery is already full ... with both plugged in my software can decide which-gets-what based on amount of Solar and whether either of the cars is below-min, or above-max.
My cars have a Charge Limit set suitable for "If it gets this low then charge overnight on off-peak" e.g. 50%, and then if there is excess Solar during the day they will top up to some higher limit (e.g. 90%)
One issue with this is that Tesla in-car CONFIG only has "Start at" (e.g. set to the start of Off Peak) and no "Stop at", so it won't stop when Cheap Rate ends. People (manually) set the Charge limit to, say, 30% more than current, in the knowledge that 30% overnight charge neatly matches their 4-hour off-peak tariff. Bit of a faff though ...
I use a 3rd party APP which stops the charge at end of Off Peak(*). That brings the 1st World Problem of the rare occasion when car will not be fully charged "tonight Off-Peak" and tomorrow I'm going somewhere which needs more charge. I haven't found an APP that lets me neatly override the default behaviour (but the API is well capable of allowing that type of "stuff" - "
Alexa, make sure car is charged for 240 mile journey tomorrow")
I appreciate these are problems that arise more in a 2-EV family, but I suspect that for all current 1xEV +1xICE owners that is just a matter of time
In terms of Tarif I think the choice is for a 4-hour slot or Ecoonomy-7. The 4-hour slot will be a cheaper rate, but for a high mileage drivers may not be long enough. EVs will do 3 - 4 miles / kWh and there are some charging losses ... so 1 kWh in the battery might be 4 miles, but it might need, say, 10% extra "from the grid". And my driving style rarely gives me the full 4 miles
So ... a 7kW charger and driving 3.5 miles per kWh works out at around 25 miles per hour. 4 hours is 100 miles ... if you do more than that each day you need something else - either Economy-7, or charging-at-work so you only need to get there, and not back as well! If you do more than 100 miles once-in-a-while then let the car fully replenish over 2 nights, or on those rare occasions when you have "
another long distance trip tomorrow" do some charging at Peak-Rate.
If you are going to have Solar PV then that car (or at least "One of them") needs to be at home on sunny days to make use of excess solar. Or you need a House-Battery
(*) The APP also does things like "Change to AMPs=32" ... during the day my car-charge AMPs for Solar may drop so that the car charges at about the same rate as PV generates ... but if that remains at, say, 5 AMPs then when I do actually want to charge overnight its helpful that my APP will actually reset to 32AMPs - otherwise I would get caught out!