With LGDs the rule is to introduce them as young as possible. Maybe I am moving too fast with Arthur. LGDs are meant to live their whole lives with livestock/poultry. I have never owned a dog, worked with loads of them, yeah, but he's mine(Still can't get over how awesome, and tiring it is!) and I think I may be too focused to make him "Perfect" with everyone and everything and wanting to get everything right, when even I know there is no such thing as a perfect person or dog. And he is just a puppy! I definitely think I may have been expecting too much of him too quickly.
Reading the replies kinda got me back to my original mindset. And in just one day it is already proving to be better than me trying to rush him to be perfect. I even let the kittens out a few minutes ago and not once did he try and grab them. That has never happened before. I'll need to try and get a few pics. It was awesome!
Cheers to a long happy friendship with Arthur, puppies are awesome.