People have done truly remarkable things is areas a quarter of what you have. It's all about planning and observation.
It's a very good idea to start off container gardening. You can grow some stuff while trying to figure out what to do with your yard.
My wife and I did just that. We had several containers going while observing the yard for about a year.
We made a map of the back yard and plotted the sun through the four seasons. From that we were able to then figure out what does best where. We get a very good chunk of sun for most of the day. So that is were our raised bed are.
when planting anything read up on it's sun and water needs. then see if any place in your yard matches those requirements.
For example we planted our blackberrys on the side of our house. That only gets at most 8 hours of sun. But that is plenty (probably a little too much lol) for the blackberrys. Last year was our first yield and we had quite a bit. They grew very well and this year we should at least double our yield.
Berkeley, if I understand correctly, can have fickle weather. Some days beautiful, some days cold, rain on and off. This is perfect type of weather for berry plants. You are right on the mark with blueberrys.
But there are a whole variety that you can plant in that zone. We live in zone 8. Hot. Lots of sun, little rain. So it's always a struggle for us. It looks like Berkeley is in the 7a zone.
http://www.usna.usda.gov/Hardzone/hzm-sw1.htmlYou can do a whole lot. But obviously, don't limit yourself to only berrys. LOL I get my seeds from a place local but a great online nursery is Millers. Get their catalog, it's free. Just reading through it will give you a quick education as to what is available to you.
Look at growing stuff in pots, like you would in growing stuff in raised beds. In a way, they are very similar. The benefit is: you can control the soil. The thing with pots you have to be aware of is: drainage. Not to much, not to little. Use a good soil. And make sure you put some rocks in the bottom.
Herbs are take virtually no effort. Just make sure that what ever sun they do get, it generally is not more that 5 hours. Herbs do very well in shade. (but you probably know that already)
How are you making your raised beds?
As far as your extra space. You may just want to leave for a place to sit and enjoy your garden. I did that purposely in my yard. I like to be out among the plants. :)
I like the idea of your zukes and squash spilling over your fence. I don't know how many people there are in your home, but between my wife and myself, two zuke plants do us very well. Otherwise you will be making A LOT of zucchini bread. lol but it never hurts to give the extra to neighbors. Could inspire them.
If you feel guilty about tearing out the landscape, then don't. Enjoy it. Slowly replace it. If there are water thirsty plants there that are killing your water bill, one by one replace them.
As far as water saving, the water tanks I have used to be food beverage syrup tanks. I know, ick. But they are large. 4 x4 foot print and 6 feet high when raised off the ground.
If you want something that large, you have to plan for it. just a little heads up.
You can prune back the persimmon. It's a pretty tree and works well with migrating birds. Avocado's are gender centric. You will need a pair of them to generate any fruit. I found that out the hard way. LOL
Given everything you stated, I think you will have no problem growing anything. I think your only challenge will be dealing with rain (over abundance) and quick changes in weather.
I hope some of this helps. I'm by no means an authority, I just have gardened for a long time. :)
Cheers.