Let's be honest, since sacks are in game, how often do you use wheelbarrow for anything? i justify it in only one case, packing raw hides on racks. so how about we not let this cool item be forgotten?
so, the idea: when you 'drive' it, somewhere (preferably) low on screen you get a list of stacks inside the wheelbarrow, cause yes, i want this heavy duty item to carry multiples of stockpiles at once. say, six to be merrily adjacent to carts. this new bit of ui at the bottom displays with icon and/or text the types of stockpiles inside it and mouse wheeling over this bar scrolls which (center) stack is the current one to place down.
and, for this to be an idea even worthy of using in game, we need a metal upgrade version, just picture modern wheelbarrow for concrete works and slap wooden wheel on it for good measure. to carry 9 to 12 stacks, up to dev's mood.
i'd agree that letting this item while filled to fit in cart would be too much, so lift only transport i suppose.