Would be awesome to have something like /wild unit, but for /stand pose
So we could have an armour stand using pre-set of a few poses.
Maybe a plugin could assist in this.
Looking at the unit, then type: /stand pose [1,2,3,4]
1- default
2- small
3- arms/noarms toggler
4- fight
5- ...
If an option to hold a sword, shield, etc is possible, perhaps it could use what you're holding in your hand, or have available in your inventory to populate it.
Breaking the armour stand should just drop the items and forget that unit.