fishing doesn't come close to building looms, LP-wise. line, hook and lure can break (supposedly the pole too, but never seen that happen), and if they don't, your inventory flows over. as far as I understand, with full inventory and one final fish on your cursor, you don't get any more LP. although writing a makro to go fishing and dump the fish on the shore sounds really tempting.
but branches are plentiful, fast and easy to gather, and actually regenerate, which leads to loom spam. and finishing them isn't a real option either, unless you literally excrete string type items

just being able to move or destroy construction sites would solve several problems. adding the pavement requirement to looms would also severely reduce the LP gain per time spent.
"Если не я за себя - то кто за меня? Но если я лишь за себя - то что я? И когда, если не сейчас?" Хиллель Старший.