I am partial to Evening Blue, but that is a taste thing. I think color adds much to the visual appeal of a home, and white trim with blue siding is a crisp and lovely combination to my eyes. We are currently planning a custom new build and plan to use Hardie Evening Blue with white trim and a bright yellow door. This photograph from the Hardie website was one of our inspirations:

Thanks @Emily - that's a beautiful color. But it's a little brighter than I'd realized. I wonder if it's a too much for my crummy little house. I liked the blue-green-gray vibe as in the photo below, which is also supposed to be Evening Blue.

HardiePlank Evening Blue (Fanwood, NJ) · More Info

My best option might be Iron Gray, like the one below. It's dark but it also has some color at least from the photos I find here on Houzz. I worry that I don't see a lot of very dark houses though, and there must be a good reason for that.

James Hardie Siding in Wilmette, IL · More Info

Okay, here's my crazy bad mockup of what the house might look like in Iron Gray: what do you think?

I like it. I think dark-colored houses are attractive! I see a lot of them in neighborhoods near me, which ha e a mix of newer and older homes. For some reason, a lot of new neighborhoods seem to stick with whites, creams, and beige tones, but I like the contrast of a dark siding with white trim. Go for it!

Night Gray has more blue and is not as dark as Iron Gray. I am replacing my home’s siding w Iron Grayy and black trim. I'm afraid it will turn out a little gloomy or it could lean as more artistic. Recently, I have seen beautiful iron gray monochrome homes that were inspiring.

I like the grayish bluish color better than the all gray. You have a lot of trees that make it look a bit darker and have a gloomy look. Brighten it up and have a happy house, rather than a sad gray house.

where is the black trim