First, your feedback is much appreciated. As you'll see below some of your issues are new issue and likely would not be noticed and fixed for a while unless someone such as yourself reported them.
The first two issues are new to me as I've not yet heard of them or seen them prior to reading this thread. Can I assume that you are using the rich text editor when you encountered these issues?
Your third issue is a known issue that was brought to my attention late last week, I don't believe I've yet had a chance to create an issue in the issue tracker for it yet. I'll update this thread with a link to it once I've had a chance to do that.
The forth issue is an unknown issue however it does make sense because of how the html from the gui editor is converted to wiki markup when the document is saved to the database. I'll also create an issue for this.