For me, what separates Hans from other models is his Ruthless and the ability to have the triggers guaranteed. If I play against a keyword with much Manipulative, Terrifying, or a master that needs to be pinned down, I would really consider Hans. I had games where the opponent selected an aggressive master, so I took Hans just to repeatedly give them stun and slow.
Also, you need to consider your terrain. If you think that you will have to move him many times in order to be in LOS of your target, then better replace him with something else.
Last but not least, I sometimes use him for