As your request appears to be an oxymoron would you car to explain what you mean by 'woodland look'?

I'm trying to approximate, as closely as possible, the look and feel of woodland....deep greens, cool lushness, broad leaves, fern-like, etc, knowing full well it is an oxymoron, but also knowing it can likely be done to "some" degree....just as a tropical feel can be loosely approximated and translated to low water garden usage, by using plants that have a lush feeling, such as phormium, drought tolerant bamboos, alyogne, agave, senecio etc.

My preference is towards a more tropical look than a woodland look. Some of the images below might be helpful . I noted the plants that can adjust to low water needs.
If you are located in the Pasadena area, take a walk thru the Lummis garden.

A fair amount of California natives will fit your needs such as ceanothus, ribes, manzanita, arbutus and our native ferns - check out Las Pilitas website for inspiration.

myoporum ground cover, lorapetalum, woodwardia fern, ribes , heleborus {{gwi:51533}}From Raised Garden Beds

podocarpus, libertia, choysia, carex
{{gwi:51534}}From Raised Garden Beds

In the carmel valley woodlands
madrone, manzanita, choysia, callistoma little john, geranium warleys pink, Japanese maples, Azara, chamacyparis nidiformis
{{gwi:51535}}From Carmel Valley Estate

agapanthus, lorapetalum, dicksonia, pittosporum, camellia, iochroma.
{{gwi:51536}}From random photos

Asparagus fern , Clivia, Sub acorus or liriope for water thirsty Japanese forest grass
{{gwi:51537}}From Pina Colada

Cantua
{{gwi:51538}}From Pina Colada

Abutilon, Brugmansia, Heleborus, Pyrrosia fern, Aspagus refractus, Doryanthus , Euphorbia
{{gwi:51539}}From Pina Colada

Can you bring in an arbor or some kind of shade structure? It would also give you a place to grow some vines. If you add some tropicals in the sunny areas, I think you could blend those nicely with some drought tolerant 'woodland' plants, even if these were only under the larger tropicals and vines. It sounds like a challenge, but if done well, could be a beautiful garden. Best of luck :)

It kind of surprises me that someone would be soliciting open ended design advice for a paid job. I'd feel better reacting to such a designer's thoughts and plant choices rather than being a free source of research. California's. chaparral plant community or South African Fynbos vegetation would be productive directions to research for "busy" plant communities that don't contain trees. Check out the Norton Simon Museum gardens for potential ideas as well, there in Pasadena.

I think you should redefine the look you are after and drop the "woodlands" from the description, because that implies dappled shade and actual tree canopy. Of course you could elect to use narrow canopy palms or palm-like vertical accent plants to give limited dappled shade without creating too much shade inducing canopy, especially since there are so many suitable narrow canopy plant choices for a southern California setting. Trevesia palmata and Cussonia paniculata are two candidates that come to mind.