Charles Xavier is much better in the movies.
The X-Men movies were a clusterfuck, but I have to say that one thing they did better than the comics is their portrayal of Charles Xavier and his relationship with Erik/Magnus.
Like, in the comics his dream of peace and coexistence is rooted in stubborness and egoism. He refuses to see other points of view or consider any opinion that's not his own. He's a middle aged, manipulative white man that uses his telepathy to control people and push them to do what he wants. He treats the X-Men like soldiers, some of them he grew up specifically with the intent of making them fight for his ideals. He's a shitty person, all in all.
The Charles of the movies starts as a naive young man with good intentions but a poor understanding of the world. He's kind, brave and deeply empathetic, and his experiences with his powers pushed him into wanting to help others like him by fighting to integrate them in the world rather than using violence to perpetrate a cycle of pain and fear. He doesn't create an army, he uses the resources he has and creates a school, a place of learning and acceptance. Thing is, he grew up sheltered, a white man living in a giant mansion and never lacking anything he may want. He may have faced some emotional neglect, but that's it. His idealism is born from a privileged life experience. Which is why his relationship with Erik is so interesting.
Charles has to look into the face of a man who has gone trough terrible things because of humans, who is rightfully angry because of them, and he has to find a way to explain his desire for peace and understanding to someone who lost everything to humanity's hatred. This is no easy process, which is why in the movies sometimes he sounds a bit condescending or out of touch. He's growing, he's facing the cruelty of normal people for the first time, but he's still hopeful, still convinced that if they try hard enough people will accept their kind.
Then Cuba happens, and the Vietnman war starts. He first loses Erik and Raven, people he deeply loved and trusted, while facing the fact that he will never walk again. Then he loses his students because of a new war, and everything he worked so hard to build goes to shit. He's faced with what the world is slowly taking away from him and that's the moment he loses his boyish and naive nature, and he gives up.
The movies don't make him a perfect leader. Charles is human, flawed, he crumbles in the face of pain and loss, he becomes angry and uncaring. He's still controlling and a bit manipulative, that's part of his personality. Thing is, he grows.
The whole Days of Future Past movie is about his journey in growing from the hurt and angry young adult he is into the wise and trusting professor that he will be. It's not an immediate change and he doesn't do everything right the first try, but he keeps going. He learns from his mistakes and tries to do better. I honestly loved the fact that they made Raven call him out about trying to manipulate her, and then when it would've been convenient to actually take control of her mind, when everyone was telling him to force her to do what he wanted, he chose not to.
He let her take the decision that he knew would change the destiny of the entire world, because he wanted to trust her. His hope is not the same naive and idealistic one of the First Class movie, it's something born from witnessing great cruelty and still choosing to believe people are capable of kindness. It's knowing that trust can be betrayed and stepped on, and that people can do horrible things, and still giving that trust, still giving the chance to do good. Because if you don't give that chance, than how can you expect good things to happen?
It's such a powerful message, and it's the one at the core of Charles's ideology. Which, I might add, isn't portrayed as opposed to Erik's. It's not a good against evil fight like in the comics. In the movies Erik is portrayed as sympathetic, someone each of us can understand, because he's often proven right. He is simply the other side of the coin, not evil or cruel, but the consequence of circumstances.
Charles and Erik are the true Yin and Yang. Charles looks at Erik and sees what violence and fear can do to a person, and so chooses to try kindness and coexistence. Erik sees Charles and how a mentality of peace brings to oppression, and decided to fight fire with fire. Neither is wrong or right, neither is flawless or without guilt. They are just men trying their best, it's that simple.
Their portrayal is probably the best thing to come out of those movies.