Shaving/trimming the fur around the pads is fine. I keep Nebo and Keva's feet fur trimmed short year round. Some people say huskies need it for traction on the snow, but mine get around fine in snow...the fur just seems to collect snowballs between the pads. It also helps immensly with cleaning up muddy paws, they don't bring in as much dirt when there is less fur. Plus I just prefer a neat appearance to the feet. I've honestly never thought about it helping with cooling though, I did know that they sweat on their paws but I didn't think about trimming the fur helping with that.

Sydney (schnauzer) gets shaved and the huskies tolerate the heat much better than she does. Their top coat will be hot but near the skin it is kept cooler, with Sydney the sun is heating her skin directly. Nebo does get pretty hot in the summer but as long as he has access to water/shade/indoors he's fine. I've seen some huskies/malamutes/any breed with undercoat get shaved and grow back fine....but I've also seen many that grow back weird, like thinner, thicker, or bald in places.

I looked at your photos and Koli is very pretty. For what its worth, she looks like she could be purebred siberian to me.