I'd recommend, and if you can afford it, to get your eleco to fit a dedicated 20A/30mA RCBO and put 2 x 15A outlets on it for you and use 4 or 6sqmm TPS. One for the hoist and another where you are likely to want to use an arc or Mig welder or plug other 15A device into. Like near the front of the shed so any visiting family members can plug their caravan into it for example. Even if your arc welder or mig is only a 10A device they still perform better on a 15A circuit as there is less voltage drop in the supply.
I did mine with a 15A pendant that hangs off a jack chain. At the top end is a 15A plug and a 15A outlet up high. I also added a few 10A pendants as well for power tools and the one at the front of the hoist for the battery charger for any car that is up on it.