Hi Jen
Since you're feeling like you're ready for a new challenge or direction why not brainstorm an industry or two that sounds really interesting to you, do a little research about what sorts of services would be useful and appealing to those markets and then tailor some of your networking and marketing efforts in those directions.
It can't hurt and will get you going in new directions. General admin is a great foundation and can apply to numerous niches - so choose the ones that are literally going to be FUN for you.
Along with my 'usual' clients, I decided I wanted to work with actors and authors, creatives and media personalities so I went after it and now have a very interesting cache of clients and some equally interesting projects. It's just a matter of fine-tuning your approach and putting in the effort to reach them, resonate with them, and get them equally interested in what YOU do
What industries come to mind for you?