Seeing the selection of trees you have, I suspect you'd also be well situated for pomegranates. I don't know how much profit there is in it, but there is definitely a market in the US.
Are you planning on using the rosemary and lavender as an additional crop or just as a low maintainance ground cover? Many other mediterranean herbs would flourish in the same conditions with the same care. Thyme and winter savory are the first two that spring to mind. All the herbs are great for attracting beneficial insects to your garden and the more you grow the longer the bloom season.
I like how sweet potato works as a ground cover in my garden. It might even be too vigorous, as it outgrew my squash this year. It sounds like your climate might be warmer than mine, and the sweet potatoes are perennial in my garden. You can limit your harvesting to where it won't disturb your tree roots. So far (in my limited experience) they have been one of my best plants for increasing the organic matter in the soil where they grow, even when pulling the vines for
compost.
Maybe someone has suggestions for some drought tolerant legumes for nitrogen fixation.
That actually covers the three things I think about when planning a polyculture; beneficial insects, building soil organic matter, fixing nitrogen. I grow on the home garden scale, though. You'll have to wait for someone else to chime in on the commercial level.
edit: it rhymed with what I meant to type