How exciting! I love a blue/white kitchen cabinet combo. Personally, that kitchen color combo is all over my pinterest feed.
My advice for picking colors would definitely be to try and see how the two colors interact with each other, and interact in your space. Would you want a stark white paired with dark blue, or could you opt for a light blue on the top cabinets that may appear as a soft white in your space? Definitely hold swatches together next to your countertops to see how the lighting and countertops reflecting in your space may change the appearance the colors have on each other.