Someone can correct me if I'm wrong but there seems to be no uniformity with regards to hook sizes. Especially Decoy cutlass singles which are massive.
To better explain it, take a look at the attached picture. The baker on the belly is made of Jigstar Ninja 13/0's and the tail is a Decoy Cutlass 10/0. Despite being a 10/0, the Decoy is larger than the 13/0 Ninja's.
To answer your question though, pending what lures you're putting them on to, you could probably go up to 4/0 or 5/0 st66 equivalent trebles (3/0 or 4/0 if you want the heavier gauge st76) and don't be scared to throw an 11/0 sj41 or equivalent single off the back. A single doesn't add too much weight and the weight it does put on is in the right place to help with casting and get a good tail down position in the water on your pauses. My opinion on belly hooks is to have a finer gauge with more hook than to go with a stronger hook with less presentation.
This is all dependant though on the buoyancy of your lure and also based on the standard profile stick bait being around 20cm+ in length.
It's all a balancing act you've got to get right and the more hook, the better your chances of a hook up but too much hook will destroy the lures action and turn a floating lure into a sinking one.
