Caesar shows us his arrogance throughout the play. For example in Act 1 Scene 2 he says "Such men as he be never at heart's ease Whiles they behold a greater than themselves, and therefore are they very dangerous. I rather tell thee what is to be fear'd than what I fear, for always I am Caesar" . In this quote we can see that is Caesar unashamed of how arrogant he is being. This arrogance would cause him to do other errors like he did later in the story like ignoring his wife's dream
He was great ruler because he led Rome in the right direction, but by doing so, in the process he was an arrogant and selfish ruler. He was great for Rome as a ruler but not for the people. Just like Brutus said in Act 2 Scene 1 "And therefore think him as a serpent's egg which, natch'd, would, as his kind, grow mischievous, and ill shell. " Here Brutus is comparing Caesar to a "Serpent's Egg" that is should be destroyed before it hatches and becomes dangerous if he becomes king.
They are not afraid of him ecause he is a tyrant but will become one if he becomes the king of Rome. In the book Julius Caesar manipulation seems like a varsity sport. In Act 2 Scene 1 Caesar really deceives the Romans. He is putting a show and refusing that he doesn't want the crown, even though he would secretly love it deep inside. He thinks that refusal to the crown in front of the public is a smart political tactic to get people to love him and think he less ambitious or for lack of better word desperate.
This is also a form of reverse hycology as Caesar is using it to make the crowd like him and even consider making him king as he is not greedy and hungry for it. In conclusion Caesar would be a great king for Rome but not for the Romans. He is a genius in warfare but is very arrogant which cost him his life. If he was king his arrogance would definitely be his downfall. And the romans would find out that he was manipulating them, it was Just a matter of time. He would be a very good war chief of be a ruler with Pompey but not a king all by himself.