In the world of Death Note, Light and L tend to outshine the others in terms of popularity. Because of this, other Death Note characters like Misa Amane get written off as inferior or useless to the storyline.
Though parts of the fandom often write her off as unintelligent, unhinged, and loose, Misa displays all sorts of moxie that deserves a second look. Her backstory provides a compelling reason for her dedication to Kira, and compared to many of the other series villains, she goes through some heavy stuff.
Misa Amane is actually a good character; she's not perfect, but she's a whole lot better than many Death Note fans give her credit for. As an added bonus, she adds a bit of color to a series known for being relentlessly somber.
One of the most common criticisms levied against Misa comes in the form of digs at her intelligence. In an anime full of super geniuses, Misa might not look bright by comparison, but she holds her own, as is demonstrated by her entry into the series.
Misa figures out Kira's identity before anyone else does. Some refuse to give her credit for this because she confirms his identity with the Shinigami Eyes, but the method used to find him in the first place was all her.
Misa sends tapes to Sakura TV claiming to be Kira in hopes of getting the real deal's attention, and ensures her identity stays secret by keeping her fingerprints off the tapes.
This is on the level of Light or L's plans, but Misa rarely gets recognized for it.
After arresting Misa, L and Watari force her to stand upright in a straight jacket for weeks on end with a metal bar over her eyes. Misa would be entirely justified to seek revenge for this alone, but she lets it go because she's focused on a larger goal.
Tough as nails, Misa deserves some credit for her sheer resilience.
Death Note gets unrelentingly dreary at times, both stylistically and thematically. This isn't necessarily a bad thing; why would you watch a show called Death Note if things never got dark? Still, even the biggest fan of the macabre needs a break once in a while.
Misa's brash, silly personality throws a bit of chaotic color into the mix. Watching her cling to Light while making weird faces at L can be annoying, but it's also pretty funny—something Death Note sorely needs.
More importantly, Misa alleviates the stress implicit in the mind game mentality of the series, ensuring Death Note depicts more than just two geniuses at work. Even if it's two prodigies at war, it's ridiculous to assume their bout won't affect the people around them, and Misa adds a relatable, regular element to it all.
Arguing for Misa's benevolence feels like a tall task—she willingly kills thousands of people, and seemingly does it to serve her boyfriend. But Misa's more than just Light's lackey. Misa witnesses her parents' murder, then watches the court system utterly fail to bring their killers to justice. After that, a stalker nearly murders her, but she's saved by Gelus at the last minute.
Kira, who Misa later discovers is Light, gives her the justice she desires by taking out the man who orphaned her. First she tracks Kira down to thank him, then subsequently falls for him and his manipulations.
Though at times Misa behaves in an unstable or inappropriate fashion, it may be because she's experienced multiple traumas without processing them.