Do you have an architect at this point?

We have a technical drawer, he did all the plans with us. But we are having a hard time figuring out this last piece.

I hope the experts will chime in for you. Browse the Houzz photos, choosing exterior, contemporary, two storey, mixed siding from the side tabs.

Personally, I would eliminate the 3 areas of partial stone at the garage, keep that all wood. When I see stone I want to see visual strength. Can you change the lower floor windows to be larger vertically?

The rendering has pine trees in the background and a flower bed in the foreground. Your environment might suggest exterior surfaces. The neighborhood might help as well. The point is, you can observe your location and select materials that reflect your interpretation of the environment and setting of your new home. This is the work of a creative professional usually. There are no points deducted by consulting a creative professional designer now, or making the choices yourself. Keep in mind that "creative" means "thoughtful" in this context. And understatement is often a safer opportunity. Technically, consult with some contractors soon, the envelope of a residence is the single most expensive element.

Thank you for your both your advice. We were on the fence to hire a designer, we will now ;)