Is it possible to map doubleclick on folders in Finder List View to Expand/Collapse triangle? I really hate all these windows cluttering the desktop, and spring-loading isn't a big help. So to have a more Windows-Exploreresque view, I try to use the collapse/expand triangles in List view only, to be able to sort my files properly in the folder hierarchy.

I installed XtraFinder to use Return for opening files (please raise your hands if you like cmd-o to do that) and Navigating back via Backspace. But my motor skills are very hard set on doubleclicking folders or hitting enter to expand them.

Is there any way, to never "open" folders in new windows/same window, but to toggle collapse/expand always instead?
I'm raising my hand…  

 Return ⏎  or  Enter ⌅    is to rename,  Cmd ⌘    O   or double-click is to launch or open.

The Finder is the most beautifully key-commandable environment. Just look at what you can do…

OS X: Keyboard shortcuts (Finder is towards the bottom)

Very simply, in List view  →  &amp;  ←   will open &amp; close the current folder, add the  Option ⌥  key to recursively open/close all folders in that folder simultaneously.
 Cmd ⌘    [   or   ]  will go to the previous or next folder...