The Amazing Spider-Man is a slightly different type of superhero film. It is not primarily about Spider-Man - who does not appear fully within the movie's first fifty-four minutes - instead focusing on the man beneath the mask, Peter Parker. Though most superpowers or powered suits are extensions of the users, Spider-Man has an entirely different outward personality from Peter. To pull this off, the writers had to focus extensively on the human characters in order to rouse the support and sympathy of the audience.
Peter is very approachable, yet standoffish enough that he does not easily make friends. He is striking while generally blending in. Note that Flash is mean to him only because Peter treats him like he is inferior, and that is only because Peter wants to save others from Flash's bullying by making himself the target. As Peter purges his frustrations through his deeds as Spider-Man, he becomes more of a visible high school presence (in multiple ways) and shifts his wardrobe from heavy layers to T-shirts. His superhero persona allows his anger and dejection to be lessened, initially through vigilantism and later through his accepting his role as a heroic figure. One gets the sense that without an outlet, Peter would be a mopey, lonely teen. Another major factor in his personality growth is his relationship with Gwen.
Gwen Stacy is a likable female protagonist and a woefully uncommon one. She is extremely intelligent - top of her class, Oscorp intern, first seen reading Vonnegut - while being feminine and flirtatious. This even extends to her wardrobe. Instead of high heels and high-maintenance hair, she sports practical boots and pulled-back 'dos. Rarely do movies feature heroines brighter than the (super)heroes, Harry Potter's Hermione being the most famous example. Gwen's position as an intern to Dr. Connors also allows her to be integrated into the main conflict in an organic manner.
Dr. Curtis Connors is probably the most complex character amidst the proceedings. His back story is one of loss like Peter's, yet those he has lost and his methods of coping are very different. Where Peter turns to heroism, Connors shifts to villainy that he believes is heroism. Peter is haunted by the deaths of his parents and later uncle; Connors has driven his wife and child away due to his fixation on his missing right arm. He still wears his wedding ring and (a questionably canon) deleted scene reveals that he has a young son. His fallible humanity spurs his transformation into Lizard, which manages to walk a fine line between evoking empathy and revulsion.
Lizard has regenerative capabilities, making a battle against him nearly impossible to win. He can be temporarily halted by freezing, yet Spider-Man cannot defeat him while his serum is still working. Spider-Man must rely on evasion in Lizard's underground lair, during the school fight, and in the skirmish on Oscorp Tower's roof. Instead of the typical hand-to-hand or weaponry melee, ASM's action sequences rely on blocking and escaping, with a lot of webs expelled and swung upon. While this could be tiring, the changes in location and strategy keep each scene unique while allowing classic comics-Spidey poses to emerge.