The center of between the grip(handle), and the strap (arm holder) is not at the center of the shield. I think this off centered placement looks a bit off.
So, I think it would be looks better, if center of between those are placed at the center of the shield.
Why would any self respecting Dawi hold shield like Umgi
Dwarven anatomy. Due to the thickness of his upper arm, his elbow would stick out if the strap was further to the end of the shield. The most effective way to hold such a shield, is when your lower arm is sort of in the center of it. The exact position of the strap is not so important.
I think the purpose of having a big, ol’ round-shield like that for a dwarf is that you want it sticking out to the left. If dwarves are any good at creating a shield-wall (hint: it’s their schtick) they’ll probably utilize the same shield-wall style of the Spartans/Romans, allowing for each soldier to brace their own shield and the shield of the dwarf protecting their vulnerable flank (right side in this case).
If it’s anything like the Spartans, the purpose of the off-center strapping is to cover the dwarf you your left while leaving a more convenient gap for your right arm to swing over.