We only have our one Model S. Nobody liked having to drive the Prius, so we sold it.
There have been a few times when it gets complicated, but it's not hard.
If we had two, I can wire another 14-50. Both cars can plug in at the same time. The timers could start one car at 10 PM, the other at 2 AM, and both could recharge, with no problem with appliances.
We live fairly close to three superchargers less than 50 miles away, different directions, but we always have a nearly full tank every morning, and that's a lot of miles. With no planning, we can head out and drive 200 miles and never even think of charging. Arriving at home, if I needed to, I could make it to a supercharger and go on in any direction. It's something you get used to. You don't even think about going out of your way to a gas station.
The idea of not being able to wait for a supercharge interests me, since I watch people who are so very much in a hurry, dawdle around before leaving, or when they arrive they stand around talking for a half hour. I see people drive like maniacs, literally, passing on curves, on hills, going 20 mph over the limit, to get to their girlfriend's house so they can sit and watch TV all evening. You know what I mean.
I am not saying that is everyone. Some have to move out quickly, but even in my hospital, I see people screaming into the parking lot, and then taking a half hour to get into scrubs. Most of us profit by having to slow down at a supercharger for 20 minutes.
It's an easy mindset to get into. But if it's not for you, and you can't do it, then you gotta use gas, while you can.