A real suit coat deserves a real hanger.
A contoured hanger—which is often wood but can come in plastic as well—maintains the natural curve of a shoulder and the shape of a coat. Wire hangers flatten them unnaturally. Trousers don’t deserve to be draped over narrow wire either, where they’re more likely to crease. A half-inch wide plastic number can do the trick, but a one-inch wooden hanger is better still, and looks terrific in your closet. What’s good for your suit is good for your morale.