In order to remove the extra spaces in the cells in the pdf document and other changes, you will need to edit the Normal.dotm template. The spacing is determined from the Normal.dotm document which is typically located under C:\Users\<username>\AppData\Roaming\Microsoft\Templates. You can open this document and change the line spacing options under the Paragraph section of the Home tab. When on the spacing dropdown, you can choose Line Spacing Options and select Single spacing and click the Set As Default button. This should take care of the spacing issues on the PDFs, after saving the changes to the Normal.dotm document.
You may want to create a backup copy of the normal.dotm template first just to be safe. Here is some documentation on editing the Normal.dotm template:
Note: We provide links to third-party websites in an effort to help you resolve your issue. We are not responsible for the information on third-party websites, and we cannot assist in implementing the solutions on these websites.