We are working on improving the documentation on an ongoing basis. One of the improvements that our documentation team is working hard on currently is adding version numbering to pages in the documentation to make it easier to determine what version(s) of the Engine the page applies to. Another area where I believe we can do better is in regards to communicating specific API changes between versions in the release notes. There have been some discussions internally about how we can do better in this area, so I am hoping you will see improvements here as well.
If there area any specific areas of the documentation that are troublesome for you, please feel free to create a new AnswerHub post about them. We can then bring that up with the documentation team to see if those areas can be improved. Unfortunately our documentation team is rather busy, as I am sure you can imagine, and depending on the area being addressed, improvements may not be possible immediately.