One thing I think is handy and that I want to explore more for a wheelbarrow is where the wheels are located.
I have a large truck at work that we call the tippy truck. It's used every day for carrying a large quantity of bin bags and any time a contractor is in that needs to move things around, they like to use it. It has two wheels but in the centre.
It's pretty similar to this but bigger:
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It's great because it takes all the weight on the wheels as long as you keep it balanced, whereas with a standard barrow with it's front wheel you can end up with orangutan arms.
There are versions with an extra wheel front and back and I've thought it it would be handy for those times it's unbalanced.
The henchman you have looks like it could work in a similar way as it's got a good size to the front of the tub.