Too many people think AWD helps with stopping or steering, that's not what it does. So when navigating hazardous conditions, it isn't a safety option.
AWD helps your vehicle move, which can get you out of places you might get stuck, but once you're moving, it's up to your tires. Hence getting snow tires > AWD on all seasons.
RWD is off menu due to battery constraints, they simply make more profit margin off of AWD since the cost of the motor is something like $800 or less. That said, $2000 isn't a lot more for more power (over a 3 or 5 year term).
If this is make or break, then don't exceed your budget. RWD has longer range than AWD, weighs less, and costs less. While AWD can be more fun with faster acceleration.
Here are ranges based on a dyno (important to elevation and wind patterns don't change results) so you can compare ("D" = dual motor):
Tesla Range Table - Teslike.com
RWD should be EPA rated at 332 miles, while AWD should be listed at 309