I don't think whether Angela is or isnt given Dr Manhattan's powers is important. I do think "fans", on a basic "narrative level" need Dr Manahhattan and/or his powers to enjoy the narrative. Thats why he ends it that way. But whether she does or what she does with them if she gets them is not this story or a story he wants to tell.
I think Veidt gets arrested because thats Silk Specters job. It's suggested he put her lover, Night Owl, in jail. I agree she needed more to do and I certainly want to see her being Silk Specter or the Comedian or whoever she was after the first narrative ended, but she does bring forth the ideas and the parts of the narrative that explain cops are wearing masks and what happens when they break the law.
Comic book villians are suppsed to be comically evil and white supremacists are usually, well, comically evil. I still think they came across as human beings.
Whats the deal with the masks? Its all a metaphor for our collective trauma as a nation. Our history of slavery and genocide and the lack of healing from those crimes. So he makes the first superhero black and angry and tells the story of his victimazation. The one aspect I was annoyed with is the "hyponitizing" of black on black violence. That didnt need the sci-fi element and they never really showed that beyond that one episode. Humans commit those crimes agaisnt their own communities because they powerless to take out their anger on the instution that marginalizes them, not because they are hypontized.
Finally, why make this show? Because its a big IP. Its a miracle he could make the story he did. Fom cold war to race, its kinda brilliant.