Choosing a replacement for Finder
Most of us are perfectly happy with the built-in Finder app in OS X, particularly with the Mavericks enhancements which include tabs. But there are several enhancement apps to add to Finder's functionality and, even, one complete replacement for Finder in Path Finder. I've used Path Finder off an on for some years. While Finder is dumbed down for the majority of users and does not allow diving into dangerous waters, Path Finder needs to be approached with caution.
Harry Guinness's excellent Tuts+ tutorial guides you through all the options:
Path Finder allows you to totally customise the interface. It is built around a series of six modular panels that you can configure as needed. In addition to standard file browsing panels, you can display a number of panels showing information about your files. Path Finder also features the ability to create new files, perform basic image edits or connect to Git and Subversion. On top of all this, you can even include a Terminal window directly into the interface. And I have barely scratched the surface of its features!
But he reckons most people will go for one of the two alternatives, XtraFinder or TotalFinder. If you find your Mac's built-in finder lacking in features, read more here.