I love this outfit. The coat is impressive. Substantial. A statement even though it is a neutral. Worth the money you spent.
I like it with the culottes and do not think the length is an issue in this case. I do find with dresses, I like the coat to be the same length (or longer) if they are flared at all (A-line or full skirts) but if it is a straight skirt or pants, it seems easier to get the proportions right if they aren't the same length.
You're right that it is much, much harder than it used to be to get a good quality wool coat. I do own a couple (and one lower quality one that is a blend). Alas, as others have said, our weather gets so nasty that puffers are pretty much a necessity if you have to be outdoors for very long. Or if not a necessity, at least a much more practical and comfortable choice. I agree that wool is wonderful as a base layer and layered over top, and I can do that and wear my wool coat if it is around 0C and I'm not outside too long and it is not heavily snowing....but once the thermometer goes lower, the wind picks up, and the snow begins to come down in gusts, wool can get realy heavy. And sometimes smelly. And sometimes just doesn't provide the warmth.
I think this is part of what explains the fashion for down coats; it's a bit like skinny jeans. They might not look great on everyone but they do the job. Plus, down coats are usually washable, another factor here, where you are likely to be splashed by dirty, gritty slush if you are commuting. ;(