4) a seat heater ALONE is useless in frozen cold, you need much more, and much more means much more power...
6) some example: I have an EVC300400300 witch offer also a bad integration with my p.v. (bad, because badly designed by Victron), I do not count how many times my car refuse to charge or by EVC refuse to allow charge because of crappy communications between the two and ZERO control on my side. I have HA who handle as much as I can in the actual crappy state of crapIoT but nothing I can do with anything not made to be integrated. Cars actually are one not made to be integrated, even if they offer also V2L, crapplications for remote control and so on. The are just designed as a rolling data collection device, controlled by the OEM not the formal owner. To came back on topic I simply can't makes my car heat the battery when I want it heated to use it in the early morning, there is no way to do so. The car decide autonomously when to heat and the EVC decide autonomously if allow it or not, so the resulting behavior is NOT MUCH BASED ON ACTUAL TEMP but on random interaction behavior between two badly designed devices. That's is.
7) it's not a matter of mere horsepower or torque, with a mechanic gearbox I can dose the torque, with an EV I can not. It's the same when parking in tight places, arriving slowly to nearly kiss another vehicle bumper is easy with a mechanic gearbox, next to impossible with an electric motor. At least not if I can't both accelerate and break a little bit in absence of something better.