Since you are growing with artificial light, you may run into problems growing tomatoes and peppers together as the toms are a lot taller and will force you to raise the lights which means less light for the peppers.
I can't speak to dwarf okra, but when I've grown the regular stuff it seems to shoot up a lot quicker than anything else. This again will affect light height and may, or may not, cause problems.
When I grew herbs I used DWC, but the containers were anything but deep. Maybe 4" walls 1/2-3/4 full.
See the plant on the right, below;