Many programs end up adding so many small functions that in the end they can't perform their main purpose properly, and they are no longer comfortable to use. Evince hasn't followed this path, and is still one of the most quick PDF file readers to work with. That is one of the major reasons that its Linux version is normally included by default in many distributions.
Evince's interface is very simple, with a large area where we'll view the document and on the left, a list with the pages as thumbnails or as an index. How it works is quick and simple, and the capacity with which it shows the files in its clear interface will accomplish that you no longer pay attention to applications that offer many useless options instead of maximum simplicity.