How do I make myself the default home person?

You can choose the Root person to be the one highlighted when RootsMagic is opened at Tools>File Options>General Tab

"Start person when opening this database – Lets you select who the starting person will be each time you open the database. You can choose from the root person selected above or the last person highlighted when you last closed this database."

You will need to click on the "Root person" button and select yourself. Make sure the option "Root person above" is set in the drop down box for "Start person when opening this database". Click "OK" to close.

Once you've set up the root person, you can use Ctrl+Home (or Search > Go to Root Person) to navigate to him/her in the various views.