Do you have a specific goal in mind? Or an inspiration photo?

My closet is smaller, if that makes you feel any better . . . probably not. I took advantage of The Container Store's annual sale of Elfa closet components, including installation. I now have a two-tiered rod with shelves that hold metal mesh baskets. They hold underwear, pjs, gym clothes, scarves and handbags. I also have an inside door-mounted shelving system intended for pantries that holds my shoes. Boots tuck in under the hanging clothes.

I think the Container Store has a big Elfa sale in January -- maybe 30% off??? I find the products to be good quality at a very reasonable price. If you bring them the closet measurements they'll work with you on design. Check it out.

Very shallow! The back wall is 71.5" wide and 44.5" deep. There is a door, the walls next to door are 20"

Having the rod wrap around the side wall actually decreases your amount of usable storage space. You want just rods/shelves along the back wall. No need for a fancy closet system, IMO. But get the kind of wire rods/shelves that attach to studs via these: http://www.homedepot.com/p/ClosetMaid-ShelfTrack-84-in-x-1-in-White-Standard-Bracket-2812/100194576. The brackets that hook in are adjustable. You can do double rods except for a small area for hanging long things like dresses. Then put hooks on the side walls for belts, bags, etc.

To take advantage of more vertical space, I suggest you find a large shallow plastic box for your sweaters, then fold and file each one vertically instead of stacking on a shelf. You can raise the rods and shelves you have up a few inches, but still at a height where you can grasp a hanger, with any luck. Then put the sweaters below the tops. Walk in closets that have exactly one neatly folded sweater per shelf are rarer than hen's teeth. What happens with the setup your closet has is that sweaters get piled on top of each other and yanked off one by one until someone gets annoyed and refolds them all six months later. Putting them vertically in a drawer or drawer-like box will mean they are easy to find, they stay untangled, and they don't sag.

Yes, a closet purge may be a good thing to do. The Marie Kondo best seller, http://tidyingup.com/books/the-life-changing-magic-of-tidying-up-hc is worth reading if you feel like you are pressed for space.

You have things very well sorted by type and color already. Hanging slacks from the waistband is awkward. If you want extra neat and uniform appearance, hang all the slacks on your nice pants hangers so that they are folded the long way (not crosswise at the knees) and the curved back side is against the wall, and the smooth front side is toward you.

Leelee, I think the best solution would be to install a standard closet organizer on the back wall that will give you a double rod on side and a single rod on the other. The section with the double rod should be larger than the single. I would then add another shelf on the top if you have enough vertical space left.

Then on both side walls install narrow shelving from the floor to the ceiling - these can hold folded sweaters, tshirts, shoes, bags, etc. You need 24" for the hanging space, so that would leave you 20" for shelving on each side.

A closet system is a great tool that organizes many items in a closet. This report is very useful.

http://mooredesignstore.com/closet-systems-are-worth-buying/