Basically the issue you worry seems to be tailgating on freeway.
Try to avoid using the fastest lane, except for passing for a short time.
You will feel more relax and rarely will you have someone tailgating you.
I never experienced phantom braking but it seems on freeway that approaching an overpass
might trigger some false positive, thus provoking some phantom braking.
I only noticed that FSD slowdown when approaching a green traffic light.
A good prevention is keeping your foot on top the accelerator pedal to avoid having your car suddenly slowing down.
On long distance driving, like between LA and SF, most of the freeways have only two lanes, so you don't have too much choice of lanes.
But a FSD feature that I like is the automatic lane change, so if you notice someone tailgating you,
you can just put your turn signal to indicate that you will merge right when possible.
And FSD will then proceed when safe to change lane, so you don't have to keep constantly
your eyes both on the road in front of you and in your rear view mirror.
Putting your signal earlier will prevent someone trying to pass you from the right, something difficult to notice.
Driving an EV, like a Tesla, is so relaxing, you will enjoy it and when needed, you will still have a lot of power, especially with a Performance version.
You don't have any turbo lag or gear shifting, and in curvy roads you will appreciate the four wheel drive instant torque.
