Sounds like you've done some research and are starting to figure things out for yourself.
The big rods should do fine for sharks and rays. In some of the bays and on calmer beaches Bat Rays can be a kick in the pants. They rarely jump but will take off on runs that will have your drag singing. A whole California Squid fished with a slider rig on the bottom will get you bit. Look for calmer water close to a channel. Steel cable isn't really necessary if you use 30# or heavier mono for your leader. This will also catch Leopard Sharks and Sand Sharks.
Your grub/jighead set-up sounds fine for our Halibut and a variety of other fish around here. If you think of Hali's as Summer Flounder that can get a lot bigger, that should give you a place to start.
Tight lines,
Wade