I know you said you wanted extra space and range .. but book a test drive in the revised M3. I must confess I haven't been following the updates so closely, however I can say there's a difference between our 4 year old M3 (it was one of the first with the black window trims) and our brand new M3. It's definitely quieter!
Totally subjective however our M3 seats seem more comfortable. I know that people say they're the same maybe that's true but the M3 feels more comfortable somehow. Then there's the outside. I just can't get on with the plastic all around the exterior of the MY. I prefer paint on metal, so I prefer the M3.
Other minor points about the MY...
I'm not quite tall enough to wash the roof properly
The extra 3 inches width is quite noticeable on some roads and parking spaces so extra attention is needed.
The rear view is tiresome for me. There's seems to be a bigger difference between the rear view and side mirrors, making me doubt a little when changing lanes. I don't know if this is fact but my driving style is definitely affected. M3 feels more natural.
I find getting our harder in the Y as I have to twist on the seat then hop out. In the 3 I just stick my leg out to the floor which is easier.
My dogs can't jump in and out themselves as they are unsure about the extra height in the Y. I can to lift them in and out. In the 3 they're fine.
Weight transfer is definitely more noticeable in the Y. Hasn't caused an actual issue but I do feel I'm in van mode not car mode. I jus prefer sitting lower.
To your points....
Long range RWD might work for you. It handles great and has the longest range of all. It's cheaper than the AWD. Premium audio Vs standard isn't so noticeable.
Roof box might work for storage if really needed. Or even small trailer.
But overall I'd be guided by finances and choose whatever works for you at the time
Happy teslaring