AArggh - I realise this is just me.
But all 4 stances are wrong, just in different ways lol
Attached is the original drawing.
The stance is accurate and depicts a slinger in mid throw.
So far all of your variations are just a bit 'off' and from a practical slinging point of view just wouldn't work.
Other tan that, they're great
I'm no good with colours (don't have a favourite one and rarely remember the colour of anything), but the one far right stands out most for me.
Also has the cleanest and most even outline.
Now reproduce that with the image below, and you've got a winner
Are you embroidering these by hand or do you have one of those fancy sewing machines that you can just drop a memory stick onto with images and it does it all for you ?