I second your granddaughter's opinion about the colors especially the contrasty red.

The odd groupings of white dot artifacts are interesting. Each group is identical with regard to the number and location of the dots relative to each other. The groupings however, appear to be completely random in their locations in the image. Since you were able to get rid of the artifacts using noise reduction through the camera, this suggests that a good set of dark calibration frames will solve the problem as previously mentioned.

Just as an FYI and FWIW, I saw something in your image that I saw in an image I was working on the other day. I noticed most of the smaller stars in my image exhibited a tear-drop shape. I went back through the original individual light frames and examined them more carefully than I had done prior to the original stacking. I found the smaller stars in several of lights were quite elongated, whereas the larger stars looked perfectly acceptable. It seems the larger stars camouflaged a tracking error in those bad lights. Once I removed the bad lights, the stars were all nice and round.

I have to say I'm so jealous of your dark skies, or access to them. Light pollution on the west coast of Florida is getting worse by the week with all the building going on.

Neat shot. There are some unusual strings of dots that appear in the image. I'm not sure what can cause this type of noise, do you see them in the individual frames? I would try some making some dark frames and see if they show up there, if so the dark frames would help reduce them.

Just a few fireworks over Grapevine Lake a few years ago. I've used two methods to shoot fireworks, one of which I like much better. Method one, open the shutter for 10 or 20 seconds and see what you get. Method two, wait until the initial burst of each blossom and then open the shutter for a much shorter time. One you get the blinding white burst in the center which in my opinion bleaches out some of the color. Two my much preferred method of waiting till after the burst and getting much richer colors. Don't know which you use but give the second one a try and see if you get better results.

Getting from point A to point B on the internet can go through many "places" on the route. Kinda like through repeaters.
Possibly one of those places on your route is having a problem. I've had that happen.
I could get to everything except one location. One time it was a problem with the lookup table at one of those "in-between" places. "Is It Down" said they could get to it, but they are in a different location than I am. It got fixed. It took a bit for them to figure out which table location it was though.
One does not have a "direct connection" to the destination URL.
Something in between is hiccuping.