Which laundry detergent will keep clothes smelling great for weeks or even months?

I have a lot of clothes... Probably 300+ shirts and 150+ pants. This isn't including the hoodies, jackets, sweaters, etc. that I own. I converted an extra bedroom into a walk-in closet so that I could have all my clothes in one place. Now that that's said, how do I keep all of them smelling fresh and clean? Usually I'll go a month or two without wearing the same thing, and when I do wear it, it smells odd. I wash my clothes in Gain and use the matching softener and dryer sheets, plus add a cup of white vinegar in the wash. In the closet, I have dryer sheets places in various locations, but nothing seems to work. Any help you can offer will be appreciated! Thanks!