I use an extra bedroom as a home office. I installed the ClosetMaid ShelfTrack system. If I ever want to turn it back into a clothes closet, all I have to do is remove the lower shelves. I don't remember what it cost, but I am guessing about $100.00. I like the versatility of it; the shelves are adjustable and I can add shelves as I need. Many office type items are relatively flat, so I can maximize my space useage by using more shelves placed closer together. Then I left a tall area at the bottom to slide the paper shredder in. Here is a link that might be useful: ShelfTrack system

I met with an Elfa design consultant and they basically just put some shelves in like I have. They did give a really good recommendation for my bedroom closet with more structure and drawers and things. I'm just doing the linen closet for now. I recent decluttered and drastically reduced my clothes.

I've installed a lot of wire shelving, and I would HATE to try to get shelves into that narrow space! First, since they don't come 9" wide, you'll have to buy bigger pieces and cut them, which is a lot of work and a lot of waste. I know you said you don't want vertical rails, but I think rails and brackets supporting solid shelves would be more efficient in that space - especially since they are adjustable.

I agree with Patricia, a picture would be helpful. Have you looked at the Closet Maid components at HD to see if they would work to help you accomplish your goal?