I've seen a lot of people think of him as a selfish, obnoxious know it all whose only concern is being the king. This I think is very unfair to him.
-in spite of him being annoyed by zazu and singing a song that involves tormenting him... After escaping the hyenas was 'yeah, but where's zazu?' Instead of trying to run away even farther with nala, they go back looking for zazu. Simba then says to three hungry hyenas 'why don't you pick on somebody your own size?' He desperately cries for zazu's help in the gorge.
This tells me that he does care about zazu. Showing concern over his safety. Trusting him to help save his life....
-Simba and Nala had a strong friendship. Not just that, he'd go out of his way to save her when it would be much easier to save his life. When nala is struggling to climb up the bones in the elephant graveyard, this close to being hyena chow instead of saving himself he takes a powerful slice into shenzi, enough to draw blood and buy nala time to climb up.
When cornered by three hungry predators he doesn't stand behind nala cowering, he doesn't stand to her side, he stands in front of her, willing to go out fighting to save his best friend.
Another thing. When learning about the elephant graveyard, the first thing he does is go to see if Nala wants to go with him. He doesn't exclude her from dangerous things because she's a girl, he thinks of her as a partner in adventure.
Also when being pinned by nala, he doesn't make excuses, he doesn't call her a cheater, he doesn't get too angry... He goes at it again and the two are laughing. He's pinned again but makes no excuses.
-He loves his dad. So much that he blames himself for almost his entire childhood to adulthood for his death.
-when meeting timon and pumbaa he doesn't eat them. They quickly become friends. He sees them as equals despite being much lower on the food chain. He goes 'it's beautiful' when introduced to his new jungle home instead of complaining about it.
So yeah, I don't think lil simba gets enough credit.