The total distance of the waterfall's trail is 1.5 kilometers or just a bit under a mile...

That’s very short distance for that many waterfalls. It must be very exciting to walk and every here and there to see this amazing mother of nature. I’m nature lover and I have a special place with multiple waterfalls in a very short distance as well. Here is one of them. I’d say level 1 based on ratings from your waterfalls.
However, there are other much bigger which I would probably rate as 8 or 9. I can see you, your brother and everyone else had a great time. Great experience! I’m a soup lover as well and I bet I would end up with at least three bowls of Nipple Noodles soups as well 😆. Nice pictures!