For the model 3 and Y, I would just get the base model. They are already fast enough. They are all just white commodities and a few years down the road there will be new ones that will be much more cheaper and faster and lighter.
I agree about performance. The base 3 and Y is plenty quick. But with higher performance / dual motor AWD versions you get more range, which, depending on your country/location and the way you use the car, is big deal.