White trim is fine. For a more contemporary look, you can go dark . .

Same as walls but one tone down - uniform, so take the medium gray you selected, go one shade deeper and paint all the doors and trim in semi-gloss of this tone. Same for the silver walls too. No deeper than charcoal - and careful that you get two shades of gray (silver and the gray you pick) that have the same undertone. Benjamin Moore and Sherwin Williams both have good sites for picking colors with information on how they relate shade wise.