Okay you deploy a SharePoint 2013 Discussion. The thing is you find it a bit primitive, just a subject, body and Question link. What if you want to provide your users with a richer design you can do a great deal without having to change the master page or layouts or do anything in designer.
You can add web parts to a discussion. In this case I edit the page and add a search box.
After adding the search box each time a user starts a new discussion they will have a search box at the top of the discussion. This may be useful if you want to help users find information to include in discussions.
You can also change the fields in the discussion. Go to List Settings and edit the List Content Type, and add a column, in this case I add a URL link.
After this users can include a URL in their discussions.