Fireworks as distraction, could be easily made as launched remotely from farmhouse or other place. Or play death metal band records, surely creatures will run away. You can always take your waterfall with you. So why not to record sound of waterfall and play it using amplifier in the outside all the time ? Quite easy is to play waterfall noise with some mobile boombox. What else ? How the family lived through the winter, they were walking barefoot, too ? And what aliens were doing when is cold outside? We have no seen any fight between creatures and military, but if aliens can be shot down by shotgun I believe that military grade weapons should work ( and explosives, minefields, high voltage electricity, flamethrowers ), too. To commit such a task creatures could have come out from underground in a number of millions at once in every continent on Earth. I can believe that creatures wiped out some town or village ( like 'Grabbers' ) but not the entire civilization. Only the scale of events is overblown i.e.

Download movie a quiet place