Here's my take. Some may find it a bit out there, but I believe it's the only reasonable attitude if we want a just society where jounalists can scrutinize and limit the actions of governments.
Whether he committed rape, was "a bit rapey" or was just generally "an arrogant arsehole" is actually irrelevant to the main story.
As a journalist with a right and a duty to do so, he published information that needed to be in the public domain. The USA then threw everything they could at bringing him down, because that information was embarrasing to them.
I'd say the same if Jimmy Saville or Gary Glitter had done it. A person's character or reputation in some other, unrelated area, should have no effect upon how we perceive and administer justice.
Now, I personally believe it seems incredibly transparent that the rape issue was at the very least influenced by the USA's desire to get him, via Sweden, and he was justified in refusing to go there. But I admit I have no proof of that, any more than others have any proof that he's a rapist, or an arrogant arsehole. There's been a lot of loose, non-factual "stuff" put about surrounding him, as there always is with such a controversial person, and people tend to believe what they want to believe.
However if he's committed rape he can be prosecuted for it. If that doesn't happen then he's innocent until proven guilty.