I love this advice and would not have come up with it on my own, thank you @BeverlyFLADeziner

What type wood are you using for the top deck? The railings? Semi-solid or semi-transparent stain I hope?

I agree with Bev about the railings and deck the same color. I also don't think any gray colors would work with your house siding. Try to pick a color that is in the same color family as the siding. A brown that's lighter or a bit darker than your house.

I often like the deck to look like a continuation of the flooring inside so if you have wood floors do the deck the same color and I agree the railings to match since they are also wood . I also agree not gray

Stain all the deck and rails the current natural cedar house color. And in time paint the house the gray that you love.

The wood tone deck will look nice against the neutral gray house siding.

Thank you everyone for your great advice! I am so glad I asked because I got it quite wrong on my own. @millworkman I'm not sure about the railings, but the deck part will be pine, and semi-solid stain. The continuation of a similar tone to the house is great advice and that's what I'll be going with. Truly appreciate you all.

Youre not wrong but to me, from the photos the white rails distract from this particular architecture.

Have you decided on the house color? That might make a difference.