When dealing with "render :partial=>" lines. I find myself often typing out large sections of code/logic before I create or code the partial files themselves.
Just a thought... If you type out a "render :partial=>" line (or copy/paste an existing "render :partial=>" changing the partial file name) and the partial file does not exit yet, the name of the partial is yellow-lined because the file does not exist ("expected templates name or path.... ) of course.
How about a feature where ALT+Click on any non-existing partial file name auto creates the partial file? (just saying 'ALT' since it wouldn't be confused with a CTRL+Click on an existing partial name --- although when over a yellow-lined file name both CTRL+Click and ALT+Click are available/un-used).