Like they said, your 8# rig should do nicely for the ave. Surf caught Hali. You might bump up to 10-15# if you are thinking big.
You also mentioned shark. For them I'd go with a 15-30# rig and double that for your leader. Try to run a 5' leader with a split shot right next to the hook. 2oz of lead should be good on the slider, so long as it has flat sides. Either a squid head or hood should work for bait. If you want to get creative try cutting a flattened out hood into a scampi type shape, or a spiral. These can be deadly on both the sharks and Hali'sl, but take some practice with the bait knife, and may add twist to your line.

Tight lines,
Wade