Well, its difficult to say which part I liked most, because I feel like I liked every second of the movie! Look at Ceaser's remarkable stand in front of his crowd. I see a leader who is shouldering the responsibility of the whole group to make a call. I see a mighty fighter who is in absolute control of his followers. I see a wise man who understands the power and strength can't be mis-used. I see a kind heart that is ready to help the weak.
These same things I have seen in Lion-O abundantly. Hulk is a lone fighter so I don't see it in him. Same applies to Batman or Spiderman or Superman or James Bond - the lone fighters can't really have that mass impacts on others. Optimus Prime of Transformers have some of these (although the tone of comedy takes away the emotional depth in most cases). Captain Krik of Star Trek has some of this.
I still hear the sigh and realization of Ceaser - “I always thought ape better than human […] I see now how much like them we are.” I am just looking for a scope to watch the movie again!
Update: Last weekend I watched it again - this time with my son Ahyan Zaman