Can I make a reusable template?
Mockingbird doesn't have dedicated template feature, but reusing the same elements across pages is easy to accomplish.
You can easily group elements together to create a single element that will act as your template. If you'd like, you can also lock the grouped element so it won't move around while you're editing other elements. Then you can easily copy and paste this element on other pages.
Note that if you update the grouped element on one page you'll still have to update it on the others, but this will be fast because Mockingbird preserves the location of your pasted elements across pages.