The second two horses hind toes are WAY too long and are creating a broken back angle in the coffin joint. They need to be shortened from the front, not the bottom. If you want to trim them yourself, map the foot to the live sole using the tip of the frog as a marker and trim again. You will see just how long those toes actually are and a sole short will show you how far forward the heels are from the back of the frog (underrun) Barefoot Hoof Care - Page 1
The top horses heels actually look too long and too far forward from here. The pictures are not the best with the snow but I can see each horse has issues that should be addressed. The worst being the long back toes that have misaligned the coffin joints and are pulling the heels under the foot.