Tim Pope's vinegar.vim is a simple plugin that addresses the difficulty of using project drawers with Vim split window functionality. Plugins such as NERDTree become rather disorienting to work with when you have more than one window open in a split.
In the following example, three windows are open (and a fourth NERDTree window on the left):
When pressing Enter with the cursor in the NERDTree window, which window will the new file be opened in?
Tim Pope solves this problem with a small plugin ...