Home Page formatting issue when adding webparts

Here is the current home page and looks correct. 

However, when any other web part is added to this current page, the formatting is thrown off. I lose my navigation pane at the top the section below the quick links become squished and then everything is thrown off (pic below)

Is there anything that can be done to fix or add another web part. I really would like to get something for announcements up rather than news