IMO the only way to make this useable is to terrace it it could be pretty awesome if done right. As for the putting green you will have to mention that to the landscape designer that you need to hire right now. It will make a mess so better to be done before summer for sure.

some ideas

Just to add my two cents. try to put everything on grade. I have clients that want to build decks on steep slopes and the engineering can be extensive for decks. Also look into vedura block for the terraces because it already has engineering drawings and can move in our socal environment with earthquakes.

Hi Mike, You certainly have an interesting site, Cutting into the grade and terraceing with walls and steps is the way to go. You can find some professional help from "The Association Of Professional Landscape Designers" They will be able to provide the expertise to design and build the project with out the expense of an architect. Unless your an avid golfer I would forego the putting green and put that money into a pergola with lights, create more of an outdoor room, perhaps a tv or pizza oven!! You will get allot more use out of it.