Sorting Tray with Multiple Tray Sizes

I wanted to design a sorting tray that had flexible sizes for the containers, was large enough to sort coins, buttons, etc. but still small enough to sort screws, beads, diamond art gems, and other tiny things. Other sorting trays are useful, but with a lot of removal the ones with snap in pins or fingers can wear out or get loose. The trays in my design slide into a slot under the lip and can be easily removed to swap out or to use different sized trays. I'm working on this and would like thoughts, opinions, etc. Once I've perfected it I'd like to release it to the masses.