Very impressive indeed... skipping to the remarks:
RWD - SR - Solid Roof
RWD - LR - Panorama Roof
AWD - SR - Solid Roof
AWD - LR - Panorama Roof
Polestar - Panorama Roof
But the panorama roof of the Mustang is a paying option in the tech pack 2, no?
SR - Manually Folding Mirrors
LR - All other models Power-Foldable Door Mirrors
Polestar - Power-Foldable Door Mirrors
The Polestar's mirrors are also without a border. Takes some getting used to and I had the impression they caught more rain this way?
SR - Some unspecified speakers.
LR - B&O 10-SPEAKER AUDIO SYSTEM
Polestar 2 : Harman Kardon premium sound - I think it's 12 Speakers but could be mistaken.
They can put in a thousand speakers but if they all suck, the sound will suck

The HK in the Polestar comes with a subwoofer (so it says in the audio settings).
SR - Rear Camera only.
LR - 360deg Camera
Polestar 2 : 360deg Camera
What would the quality of the Mustang 360 be? I have only a BMW 4 of a colleague to compare to, but it seemed to lose the surroundings into blur a lot less than the Polestar one.
LR gets these over the SR for £6k:
+20kWh Battery, Glass Roof, Powered Mirrors, 8 Way Power Seats, B&O Speakers, 360deg Camera, Hands Free Tailgate, & Park Assist.
Good to see this summary. Initially, I thought it was only a bigger battery and wondered where the €9K pricetag from that came from. So there's a bunch of options, too... VW asks very little for the 58kWh to 77kWh upgrade: around €3K.
In the configurator on the Ford.be website (Belgium, here), the difference between an AWD SR and AWD ER is €9K just like for the RWD version. Base prices RWD SR €48K, ER €56K, AWD SR €55K and ER €64425 to be precise!
Honestly I'd recommend the RWD-SR model to anyone ... £10k less than the Polestar 2 for similar range but slightly less features & toys.
This competes directly with the Kia e-Niro / Hyundai Kona which many people love, but it's bigger and while the spec is probably a bit less, that large screen and cool factor I'd say makes up for it - although personal choice.
The RWD-LR seems to want to compete with the Model 3 LR, future Y, and the Polestar.
I mostly agree, but my estimate of the range of the SR is not as good as yours. The Polestar seems to be closer to the ER than to the SR. I think the RWD ER is the sweet spot. After adding Tech Pack 2, which adds the pano roof, and a colour, price is extremely close to the Polestar. You win some range, lose AWD, and the style is very different. BTW, all prices I mention are without grants, incl.VAT. So very close cars, indeed!