I’ve been using WordPress for years, even before it was WordPress actually. It wasn’t until I started using it for clients at work that I discovered how horrible the WYSIWYG editor is, since I never used it myself. Combined with WordPress’s content filter, it drove me crazy with it’s stripping and replacing of code. Using the Advanced TinyMCE Editor Plugin fixed pretty much all the problems though.
One thing I’d love to be able to change without editing core code is renaming Blogroll in the administration menu to Links, as it used to be. Most client don’t know what a blogroll is and I hate the term myself.
Speaking of blogrolls and links, I haven’t had links to other sites listed here in years. I know that I always felt bad whenever I would visit a site of a person that I considered a friend and found they removed me from their links list or never added me in the first place. So I just stopped linking people all together.