I think you've got most of the info. But I'm always happy to throw in some personal opinions FWIW...
I compared the standard and upgraded hifi and there didn't seem to be $850 worth of difference. You can probably do better aftermarket. I'm happy with the standard hifi because I have low expectations of music in a car - it's a really crummy acoustic environment with road and traffic noise. If I want good sound quality I listen at home.
The sport button is worthwhile on my Just-a-Cooper - much sharper throttle response and finer throttle control for cornering. I'm not sure you'll notice much difference on an auto though?? - autos dilute throttle control anyway. The steering gets pretty heavy too.
Definitely go for better lights. I chose after-market spreadbeam driving lights for max spread on twisty roads, but that's just me. On the standard lights, low beam isn't bad with +50% globes, but high beam puts the light in all the wrong places so no amount of brighter globes is going to help there - either add lights or go for the Xenons I suggest.
Clear lenses: 3 different places. I changed the side lights (lens and globe), imported from UK, and I think it cost $80 or so (and AUD was stronger then). Changed the crummy black plastic behind them for a much nicer checkered pattern too. Doesn't sound much but it really picked up the look of the car on my dark green one - and it was easy to do. Rear lenses I reckon look better in orange anyway - the white stands out in the red lights more than I like. The front I kept orange because they're in with the headlights, which I always have on, and I wanted the blinkers to be as visible as possible. Clear lenses get away from the "fried egg" look though...
Sports suspension sharpens up the handling quite well - unfortunately sharpens up the ride too, so it depends where your priorities lie! I'd go for the sharper handling any day - even more fun
Sports seats are a must! I'd rate even them as adequate rather than great. You can save $990 if you get them without leather patches on them, which I think looks better anyway.
Standard aircon is fine, I think. Even with the big sunroof (closed though), it held the interior cool on a 44-degree day on recirculate, and holds it fine in the high 30s drawing in outside air. Most days it's just set-&-forget. My other car (Skoda) came with climate and I wouldn't pay extra for it.
Heated front window: never missed it (again, in Melbourne).
Incidentally, the standard key does the windows-&-sunroof-open trick, as well as stores some preferences for the in-car computer.
I'd be interested to hear whether you choose the Cooper or Cooper D. My Skoda's a turbo-diesel and it's a very different driving experience, but I can't get my head around how petrol and TDi would compare with an auto box. And on the manual MINIs, the Cooper D shares its gearbox with the Cooper S, which I presume is heavier-duty but also has shorter, closer gear ratios. If the same holds true for the auto, it could make the Cooper D quite interesting! Also, the Cooper has a smaller tank than the other MINIs (to make room for the puncture repair kit if you buy non-run-flat 15" wheels), so even though it's economical it does need frequent refills.
Anyway - have fun choosing! It's one of the great things about buying a MINI.
All IMHO...
