I'm intrigued about Stannis so-called 'character assasination' because I've read similar complaints from other book readers as well. I just find it hard to believe that a guy who lets himself be wrapped around the little finger of some devious red devil whore and be roped in to all her evil shenanigans, can come across as a 'favourtie' in the book.
In the show he comes across as a spineless easily duped git, tossing aside his family and friends without a second though by falling for the sweet nothings of an overly ambitious red witch who has failed to deliver on any of her promises.
There's really nothing about Stannis in the show that screams 'king' material and yet he gets his faithful lackey Davos utter it every chance he gets.
Stannis is a controversial character in the books. You either love him and think he should be king or you hate him. Here are some reason I, and others, love him.
Stannis is dutiful.
He held Storms End for a year because that is what Robert commanded. He went against his own natural instincts to obey the law and supported his brother Robert when he and Ned Stark rebelled. He took Dragonstone, because Robert commanded it. He ruled the seven kingdoms for 14 years with Jon Arryn while Robert drank and whored. He did everything his brother commanded of him despite the numerous slights Robert gave him. Robert soiled his marital bed on his wedding night and gave Renly Storms End when by rights it should have been Stannis. And yet Stannis does his duty regardless.
Stannis is in charge
He listens to Mel's council the same way he listens to Davos. She serves him, he is not her bitch. He disagrees with her and has gone against her council in favour of Davos on occasion. The sexual aspect of their relationship is vague and up to interpretation. There is no bit where he is begging her to come back to his bed. Stannis does not beg. Stannis does not go to the Iron Bank on bended knee, they come to him.
Stannis has an iron will.
Stannis does not bend and, so far, he does not break. He will not back down. He keeps coming at the Lannisters even when the odds seem impossible. Its like the Terminator.
Stannis is a great commander.
Tywin always considered Stannis the greatest threat to Joffrey's throne even when he had no army. Stannis held Storms End with a handful of men against all the power of the Reach, took Dragonstone, Destroyed the Greyjoy fleet (who could beat the Greyjoys at sea?), took Great Wyk, Destroyed Mance Rayders army of giants and wildings even though they outnumbered him 20 to 1. Stannis is badass.
Stannis is about justice
When Stannis destroyed Mance Rayder's army two of his men raped wilding women. He gelded both of them and condemned them as criminals. Tywin orders his men to rape. But Stannis keeps his men in line. Stannis does not want the throne, it is simply the law. He is Roberts heir, incest is a crime, therefore that injustice must be righted.
Stannis has a dry sense of humour
He actually has the ability to quite funny.
Stephen Dilane does OK with the crap he is provided. But dear god have they treated him poorly.