Bulbs bloom in Fall and at Winter's end, and give quick results for the buck.
Cannot say they would thrive with you, but Camellias do bloom in Fall, and late Winter or Spring.
The same with colored-bark Dogwoods. You need to cut them to the ground periodically, or thin out 1/3 of branches, as young twigs carry the brightest colors.

I'd suggest a visit to the UC Davis Arboretum, similar climate, and they've got display gardens geared to residential landscape design that emphasize climate appropriate, drought tolerant choices with year round interest.

Some of my favorites for winter color include Helleborus argutifolius, Euphorbia characias, Ribes species, Erysimum 'Bowles Mauve', Hardenbergia violaceae, Ornamental Kale, Paperwhite Narcissus, Daphne odora variegata, Camellia sasanqua.

UC Davis Arboretum also has a web site with plant recommendations for residential garden design. Sunset Western Garden Book is another good starting point.

Alright great! I'll definitely look into getting my hands on some dogwood I've seen them before online but I've yet to find any at our local nursery. And I will also definitely go and check out the UC Davis arboretum, I love their whole campus anyways so it will make for a great day trip, thanks again!