I like the ones where the guy is sort of covering up with the shield even when idle. If you're not in combat, you can easily carry the shield like a handbag, but in combat it's imho a bit unpractical.
Resting position for the mace would certainly be low with it's head pointing to the ground. Just hanging in you hand. But as this animation is for all weapons, you could maybe place the weapon on the shoulder, that's appropriate and looks quite good.
With the slash, I was taught not to stretch too much to the back while attacking. It's a waste of movement and momentum. But hell, the native slash from above looks somewhat stiff with the elbow pretty painfully bent, I guess that could be improved. The hell I know, your slash may even look a lot better...