On the Home tab, to the right of the Paragraph heading,

• Click on the little arrow to open the Paragraph dialogue box
• Set options that you require
• Click on the 'Default' button at the bottom of the dialogue box

That should set your options as the standard settings.

You can do the same for your Font selections, too!

You can also set up multiple templates for different style sets - just set your options and then Save as ... > Template and then put a link on your desktop.