The issue with any import - so far - is charge port. Theoretically CCS1 and CCS2 use the same protocol, only the pin layout is different - so if they ever have a CCS adapter for North America, maybe there could be a similar adapter for Europe, since my car has the North American proprietary tesla port. It's one of my out-there fantasies to take my Tesla on a ro-ro to drive around Europe on an extended vacation.
But China apparently has a different charge port configuration again. So the imports won't really work unless Tesla cooperates to allow either charge port unit replacement or an adapter. I don't see a big third-party market for such adapters, except maybe for the ANZ market?
The problem with battery weight is that the whole car has to be made beefier to accommodate the battery size. The question would be - would Tesla produce a "sawed-off" Model 3 and keep much of the components the same, or completely redesign from the ground up for smaller lighter frame, suspension components, etc. I hauled a set of wheels home from the Calgary Tesla store, 1700km- those are heavy suckers all by themselves, and the hefty tires are due to the weight of the vehicle. It's a cascade effect. Weight may not be that big a deal, but it would make a difference in city stop-and-go driving... the heavier the car, the bigger the motor, the bigger the brakes, etc.
I would love for my second car to be a Tesla hatchback the size and configuration of my old 1990 Honda Civic.