My strategy has always been to strive for a clean shot and clean field dressing. Then make sure the meat is chilled as soon as possible. If it is warm weather, I quarter the deer and place in the freezer right after skinning and process the next day (no "aging" at all). If cold (under 40) I let it hang for a day or two and then process. Once, a guy shooting damage control deer gave me some that was harvested in hot summer weather and not properly cooled - it had a bad smell to it and I had to discard it. For sure, getting as much fat out also helps, as mentioned. Another factor is deer diet - deer from swampy forested areas with little or no hay, corn, or agricultural crops will have a wilder taste than deer from farming areas.
Since the whole CWD thing I have been deboning the meat and we either make stew, steaks, loin, or I have it mixed at a reputable butcher with quality beef. One would be very hard pressed to distinguish our deer meat from beef except that it is leaner and actually tastes better!