Putting branches into a Loom is a pretty unbalanced way of gaining LP, since the reward is drastically higher than the expected effort/difficulty of the task.
The solution I'd lean towards would be rewarding LP on completion of an item rather than for partial progress. Items would track how much LP they owe players (potentially multiple builders) and award it upon completion of the item.
An alternative would be to have different components weighted, so the branches in a loom are worth much less than the boards/blocks/etc.
Yet another alternative would be that each component yields a fixed LP (branches are always worth the same LP regardless of what they're part of,) but this starts to erode the unique rewards of different items.