that is nice. The only problem would be the double ended endmills.
Also I would probably want one for HSS, and one for Carbide. And a protective cover to prevent anything from hitting them. But that might lead to problems itself.
I may send that to my son and ask him to do one for me.
edit: oops, most of my end mills are 1/2 and 3/8.
the 1/2 has too few slots for me.
Maybe I can modify it. I have a ton of small as well, but they are in the akro mills drawers, I rarely use them.