I feel that any of those downsides, plus any number of unknown ones are possible if you tried to convert an ICE car to EV. If that type of conversion were common, I don't think that would be a problem to the customer though. These would be cars built decades ago with gas engines in mind, they aren't intended to work at peak efficiency with the realities of an electric engine, and that's not the point. I think the point is you can breathe new life into older cars. I would love to have an EV old school jeep wagoneer. That would be amazing