As a Clinton supporter, my reasons are a bit different than what you listed. My actual ideal policies are a lot closer to Bernie than to Clinton. The only thing I disagree with Bernie on is gun control and protectionism (maybe a few other things). The reason why I am not supporting Bernie is that I do not think that any of his ideas have a chance in hell of being implemented even if he did get elected, so why vote for him? I think Clinton is a politician to the bone and will be able to better enact policies that will gradually improve our nation. Nor do I see Clinton taking money from corporations and big business an indication that she won't nominate supreme court justices who will overturn Citizens United. She plays the political game, and I think you need to play the political game to have any sort of shot to be effective. Bernie's principle stand, while honorable, isnt going to change anything and is just going to put himself at a disadvantage. Moreover, he has no control over legislation when it gets to Congress, so I am not quite sure how he is going to stop corporate goodies getting into legislation that reaches his desk anyways.
I think the whole idea of a political revolution is ridiculous. I see no evidence of it happening. Moreover, our entire political structure and system was created to avoid drastic change, avoid revolution, and ensure that gradual change was basically the only way America was going to change unless shit completely hits the fan. Well, the shit hasnt the fan yet so we are left with gradual change. Bernie Sanders isnt going to change that. He can't change our whole political structure and get things done by his own will. Once he is president, he will either have the choice of sticking to his high-minded rhetoric and get nothing done, or make some serious compromises (if that actually becomes a possibility to do with republicans) and will then be branded a failure by the left base.
In this situation, I think a wonkish politician who plays the game will be better able to enact change than the populist with big ideas. I'll just be clear and state that this is my perspective on things. I don't know the future and don't know everything so I could be wrong, but this is how I see things playing out, and as a result would prefer Clinton in the general election.