Thanks for writing. How you treat your patio is completely up to you --- there's no best answer to whether you should get rid of your patio and start over, or lay more concrete to expand it.
The best way to start planning your landscape is to come up with a list of features you want. Decide what's important to you, then prioritize. If you're not sure how to design your yard once you have your wish list, you may find it best ot contact a local garden designer or landscaper. Many will draw up a plan at a low cost --- or give you the plan for free if you hire them to do any work.
---Justin, Senior Garden Editor, BHG.com