The standard PDF export options of Confluence provide bad results when having tables or, in certain cases, images.

If I use any other (free) PDF printer and go to print options in my browser, the result is much better. See the attachments for the differences.

Summarizing;

• tables are messed up; colums are divided evenly, regardless of the content and sizing on the page itself
• pictures; if included from external resources (other spaces/pages) can show the error notification "Cannot resolve external resource into attachment"

Overall, this makes the PDF-functionalities of Confluence limited. It is useful, but people cannot rely on it.