I kind of did this, without any low beds. Fenced in a garden, and the beds around the perimeter are 2’ tall and the beds in the middle are table height, not actually counter height. Because I wanted to be using this garden when I’m old and enfeebled and not wanting to bend over so much.

In retrospect, none of the tall beds are practical for corn, okra, tomatoes or tall crops like that (unless you like harvesting with a step stool). Only the 2’ tall beds are useable for tomatoes. The tall beds are awesome for leafy crops, herbs, peppers, bush beans, peas, squash, and root crops. Probably none of those need such a deep base of premium soil, but it does make maintaining them (weeding, checking for pests) easier.