I would bet on a version of 4 being true: Russians did what they did independently, but once they got something good through the hacking they coordinated with the Trump team to release it with maximum impact. It was done by one or two people on Trump's team, and without Trump ever explicitly approving or getting told how the information was obtained.

Part of the reason I believe this is that I think the releases were timed too optimally and spun too well for someone not intimately familiar with American politics to do. I just don't see how Russia or Wikileaks could have done such a good job without the help of experienced American political operatives.

Here's a possible path for the information: Russian hackers -> Russian agent -> Trump agent -> Trump mole in the DNC -> Wikileaks -> coordination between Wikileaks and a Trump agent -> public

That gives several layers of plausible deniability and involves very few people. It's not absurd to think that there are Republican moles in the DNC. And Wikileaks can claim they didn't get the info from Russians and at surface level it looks like the Trump team only coordinated with Wikileaks.

Anyway, fantasy time is over. But that's how I would have done it.