We use the same various techniques here in the central coast CA- very dry less than 3 inches of rain/ yr over the last 2 years, very little cloud cover. We do have city water to our home though. We are on just 3 acres.
Adding mulch even in areas we do not water directly, I believe will help because containment of movement of the water lens underground. If there is any moisture in the soil, it will be contained better, even if it is deeper than the roots of our trees and plants. I know it is there because of the survival of some of our 20-30 yr trees that I do not water - pomegranate, persimmon, walnut, toyon and all the native oaks, etc. I am always looking for ways to get all our grey and black water back outside in the ground into swales praying on their creation of a lens that hopefully builds year after year. Most all our planting is down hill from our home.
I am always covering any bare ground with living plants, native and non-native as well as mulching. Every native that I do not need to water, I know is bringing in any moisture from the air whenever possible. I strive for dense woodlands here with breaks I keep more wet. We have been here for 9 years and it has been slow, but I see more and more volunteers coming in each year, more birds, etc.
We moved out for a year after year 6 and had broken lines to an orchard we had swaled. I had mulched it - a lot had broken down and it was weedy. But, these apples, peaches and plums survived at age 6...for that hot 100 degree summer when I could not care for them. So, the frugality with which I had watered them (they grew slowly), did pay off...always such learning from our own experiences very specific to our site.
My failures have been around yield because of not making enough time for getting fertility back ---I know that if I worked harder to get my animal and humanure under this mulch, I would have improved water retention, etc. One day when we are retired and kids are out of the house.
I understand the fear of flammability especially with resinous pine needle mulch... I think the key is in having blocks of areas within drier zones you do water regularly or where you hold water on your land between drier areas. I know there is good literature I have read over the years on fire proofing in permaculture perhaps you have read. I tend to reforest in toyon, valley and coast live oak, ceanothus, sugarbush, lemonade berry, I allow coyote shrub and see a lot of islay cherry coming in under them. Then I have clusters of more water demanding natives and edible between.
We are definitely not all dialed in here... always on a path and always re-evaluating. Obviously my zone 0-2 are the wettest...but I have "rays" of irrigation from these zones to my outer zones and integrate these with our animals. Trying to move our pigs around to create little pig ponds everywhere ala Sepp Holzer, but much less impressive here due to our increasingly desertified conditions. I have hope. I also watch neighbors land... I see they have old standing sycamores that are surviving without water --we are about 400 ft higher and about 1/2 mile from the nearest creek that runs part of the year above ground.