Service is a tough one, and it varies by location. My local Tesla service center knows me and always goes the extra mile. The service manager knows me after years of coming in or them coming to me, and that makes a huge difference. My jeep dealership also knows me as I just bought a car from them. While they have also gone the extra mile to make things right, we have had issues with there work on our car and in some cases had to have the same thing done 3 times over before we finally got a refund for the work and took the car somewhere else. That plus the amount of time we have to invest taking our Jeep in for service is exponentially greater than with our Tesla.First, I find the normal car-buying experience freaking stupid. It's one of the biggest purchases I'm going to make, ever, and you want to make me sit around for an hour to do paperwork that could've been sent ahead of time and signed online, mostly so you have the opportunity to upsell your extended warranty and push your in-house or kickback-inducing-third-party financing options?
I'd be perfectly happy if, when I next buy a car (and assuming I can buy a new one), I could configure what I wanted online and get my vehicle in a reasonable timeframe, without dicking around in a sales or financing office. Being able to test drive in person is extremely helpful, though; I don't know how to best provide that without brick and mortar dealerships (although a brick and mortar dealership without adequate inventory spread across models and options doesn't really help).
Second, I think you hit the nail on the head regarding the post-purchase experience: in a traditional model, it varies tremendously by location, and in a lot of locations, you have limited choices within a reasonable driving distance for dealer service. If those dealerships don't provide a good service experience, you're kinda stuck, particularly for any in-warranty, recall, or TSB type services. And yes, you may be able to take that into account when buying a vehicle, but if you then move, you may find yourself stuck without any realistic options, and with limited recourse back to the manufacturer (there's only so much Ford is willing and able to do about service complaints, at least IME).
With the Tesla model, you should get consistent service experiences regardless of where you are. Whether those are good or bad is, in some ways, a different question, but they should at least be consistent and backed by the company you actually bought the car from.
With regard to Test drives, Tesla has show rooms where you can do that, and advisors who can walk you through the configuration and purchase process ... but the show rooms cannot sell you a car, which is how Tesla gets around all the dealership laws ... it is also what simplifies and streamlines the purchase process. Pro tip, if you want a discount on a brand new Tesla and no wait time, look for an inventory model in your local area, these are cars that were ordered, but buyer backed out on delivery. Not a lot of these but when they do come up you can save 5-10% on a brand new car, you just do not get to configure or customize it, you take it as is.