I think some folks miss a great thing about 1/4" hardware cloth, you can cut it to be the 1/2". If you make a hopper in the front of the rack and make the front part 1/2" and the rest of it 1/4" that would be fine. BUT I would definately not do 1/4" only to hold the food, may make a few rats hungry that way.
Best of luck whatever you decide.
No one missed that. Thats how my racks were setup, and my mice and ASF walked right on out over night when they ate the food in one area. Thus exposing the screen to climb right on out.