How about telling my boss to fire several employees?
Do you think your boss will like that?
My boss will appreciate it, he has repeatedly voiced his annoyance
It's not your job to tell your boss who to fire and how to do his job. You should let him do it and if the person does need to be fired he can make that decision on his own.
WTF what's so wrong in that? I'm not get fired for that.
I doubt your boss will appreciate your advice. In fact he'll see it as an intrusion. You should act like a professional and let him do his job.