I am a big lover of white puffers. I tried to buy one the past couple of years but couldn't find the right version. (As you've discovered, fit, esp. on hoods, can be an issue.) I do think it's a risk with a car, given our climate, and if you are a walker, you have to know that cars may rush past and splash you with slush. Meanwhile, on pure white snowy days the coat may not be quite as much a standout as a red one would be. (I also love a red coat, by the way).
But. There is something so fresh and feminine about white, and so distinctive in the sea of black.
Also, in my experience, puffers wash really well. Mine is down, but I wash it quite regularly and it always comes out great. (It's by Lole -- check their offerings, too, this year -- my coat feels like a cross between gear and fashion.)
Mine's the grey coat. Also in Finds some white puffers I tried that did not quite make the grade due to fit or other issues.
I probably won't buy one this year and will make due with my grey since we are expecting to move to a climate where it won't be a priority, but I think for Ottawa a while puffer would be fabulous.
Also, bags. I have this problem, too. If you like a satchel, I actually think this is good because one issue with puffers is that even if your shoulders are square, shoulder bags have a bit of a tendency to slip due to the fabric. I often wore my fashion backpack with my puffer last year, or I used my Le Pliage, which is okay in terrible weather.