At this moment in time if you want to hide the "code view" button you can use userchrome.css
Note that with v1.0.214 (possibly also in pre-releases but I haven't looked) there is no WYSIWYG entry in the "Layout button sequence" options. So without removing the css it looks like there would be no way of getting to the WYSIWYG editor (possibly a "plus" for you? )