Mandarin equivalent to 話事? In Cantonese, people often say 話事 to indicate someone is "the boss" (e.g., 你話事) or can decide some matter (e.g., what to eat, what to watch).

This page says the Mandarin equivalent is 作主, but 作主 feels a bit formal. Is 作主 really the right equivalent?
Haha, in China, at home, the woman is the absolute ruler, so try 老婆!

老板 is very commonly heard for boss. 

现在我是老板！

To be polite, you may address someone as 师傅, which is a kind of boss

Every 单位 will have a 领导, leader, boss

'boss people around' 对某人呼来唤去