Wondering why Scar has a lighter-coloredmane and fur, as opposed to the well known black mane he had in the original animated film? In real life, lions with dark manes are viewed as more attractive by potential mates. Darker manes are also believed to indicate stronger, healthier lions. Therefore, the remake gives Scar a paler, scanty mane to accentuate his scrawny physique compared to Mufasa. However, nearly all of his scenes have him positioned in dim lighting in order to make his mane appear as dark as his animated counterpart.
Related to this, he seems to grow a darker mane after he takes over the Pride Lands. This is both due to him growing older and due to his new, dominant position where he gets the lion's share (no pun intended) of the food.
If one watches the famous log scene very carefully, both Timon and Pumbaa are walking slightly slower when Simba is both an adolescent and a fully grown adult, and Pumbaa’s fur becomes very slightly greyer. The log scene is not just showing Simba grow up, but his two friends (who are much older than him) as well, which makes sense as Simba obviously spends years with them in exile and all animals grow old as the years go by.
The biggest reason Be Prepared was changed so drastically? A lot of it was insulting the intelligence of the hyenas, or remarking on their dependence on Scar. The new movie portrays the hyenas as actual hyenas; intelligent, cunning, and very much a threat. While allying with Scar benefits them, they are not nearly as dependent on him, and none of them are depicted as "stupid" in any sense (with Azizi's only quirk being he has no sense of personal space). The original song would not have fit the new portrayal of the hyenas.
Why is the scene where Simba's fur reaching Rafiki drawn out so much longer than the original scene? Because before this scene, Timon, Pumba and even Simba had disregarded the thought that living beings are connected to each other in the Circle of Life, and claimed that they should only mind their own business. This scene, in which his piece of fur crosses the desert from the influences of so many other creatures, effectively proves the trio wrong.
Early on, it's stated that Scar did once formally challenge Mufasa for the throne, with the obvious implication that this is how he got his iconic injury. Eagle-eyed viewers will also notice that Mufasa has a series of much lighter scars on his muzzle, likely from the same fight. The difference in scarring between the two really helps to emphasize how outmatched Scar is.
Shenzi is larger than the other hyenas and is a lot more menacing. That's because female hyenas are larger and more aggressive than their male counterparts in real life. Also, notice in the film she works WITH Scar, and not FOR him. This Shenzi is the leader of the hyenas, and doesn't seem like the type to take orders from anyone.
Why does Shenzi go down so easily when she fights Nala? Throughout the whole film, we've never seen Shenzi actually fight anyone; even against Mufasa, she sends her clan to fight for her. And, given that, according to Word of God, the Elephant Graveyard was a muddy spring where animals had become trapped, Shenzi had probably only ever killed animals that couldn't fight back. This was probably the first time she had ever been in an equal fight.
Not to mention that in real life, hyenas rarely actually take on adult lions one-on-one; their main advantage is the sheer size of their packs, and even then they don't usually succeed against lionesses unless they outnumber them by at least 4:1.
Sarabi being given Adaptational Badass unintentionally explains why Nala might have been the one betrothed to Simba when presumably several lioness cubs were available. Nala consistently beat Simba every time they play-fought as cubs. This seems to have been a game the cubs played often, and presumably Nala came off better then as well, which probably didn't escape the notice of the Pride. Even after reaching adulthood, Nala is implicitly the Number Two of the lionesses, only behind Sarabi. The simple reason for that is because she was the strongest and most talented huntress of her generation. Thus, the reason she was betrothed to Simba - in theory, she was most likely to produce the strongest possible offspring for the royal line. Presumably Sarabi, who nearly fought Scar to an even footing in this movie, was the most desirable of the lionesses in her generation for that same reason. And Sarabi chose Mufasa because of Mufasa's own strength.
Additionally, maybe Sarabi and Mufasa tried to start the tradition of arranging a mate for their offspring to avoid the fiasco that resulted from the Love Triangle between Sarabi, Mufasa, and Scar in their younger days.
In the original movie, Scar whispers to Simba, dangling from Pride Rock, that he killed Mufasa, at which point Simba lunges at him and forces him to confess the truth. However, the shape of the ledge would have made this jump impossible, plus the way Scar was interrogated could come off as a forced False Confession. How does the remake change this scene? First, Simba bites Scar on the ear, forcing his evil uncle to hoist him back up. Then, Scar accidentally spills the beans to the rest of the pride by saying he saw the look in Mufasa's eyes, contradicting his earlier statement that he didn't get to the gorge in time.
In the original animated film, non-speaking herbivores were drawn to have more animalistic, less expressive faces than the main characters, possibly implying that most herbivores weren't even sentient. But in this version, all the animals are rendered in the same realistic style, blurring and/or removing that distinction. Plus, one of Timon and Pumbaa's friends, a topi (a type of antelope, one of lions's main prey) has a minor speaking role and sings in "The Lion Sleeps Tonight". So the animals the lions hunt are likely sentient and fully conscious of what's happening when they're being killed. Yes it's the Circle of Life, but that doesn't mean it's pretty.
Overlooking the fact that it's fiction, technically a lion wouldn't be able survive on just bugs, no matter how much protein they have. Simba at some point realistically would have become malnourished and may have been forced to...you know.
It is also considering in this adaptation, other animals actually lived with Timon and Pumbaa, and they explicitly restricted him from eating the residents there.
At the end of the film, Timon and Pumbaa bring their friends to live with Simba at Pride Rock. Sounds heartwarming and all, until you realize that the Prideland lions don't really follow the rules of ... you know. They'd have to be alright with watching lions eat their kind. Pretty scary ...
May not be so bad. Zazu states earlier (when Scar was trying to eat him) that it’s illegal to kill/eat a member of the king’s Court. So Timon and Pumbaa may be exempt from being prey.
