The tree bar on the left is more than sufficient, and I'm on so many networks/channels that I can't make sense of anything on the buttons at the top anyway. Is there any way to get rid of them? I've gone through options and haven't found anything to do that.

The buttons you refer to would be the switchbar buttons. Go to the View menu and uncheck that. As a note, you do have the option to drag the switchbar to the side of the screen if you prefer. That's how I have it set up and I don't use the treebar.