ADDED: It is already implemented! Great! I love Sublime!
Explanation: When I code 95% of the time I look on the upper part of the screen. When I come to the end of the file, I have to look down or add many line breaks to keep my eyes on a comfortable level.
So, "Virtual space at the file bottom" feature solves this problem.
Please see attachement that illustrates this idea:
Customer support service by UserEcho