Re: PSC34 power generation/storage solution?
If you plan to have a deep cycle spare, you might want to read Nigel Calder on batteries - he contends it's better to combine all of your batteries (except the starter) into one house bank. It's easier on the batteries and simpler to operate. We used a Blue Sea Add-A-Battery switch to parallel the house and starter batteries when a charging source is present or when the combine function is selected.
By the way, the Calder reference is the Boatowner's Mechanical and Electrical Manual - highly recommended if you work on your own boat.