The current button follows the menu of Questions | Tags | Users | Badges | Unanswered | Ask Question
It looks okay but I feel like these are more navigation links than a button as important as asking a question:
To me I love what you guys did with the buttons like this one:
So the Ask Question would look similar:
To me this now becomes an action rather than some navigation link, it stands out more, and it distinguishes itself from going to existing questions. It's a signal to the user and I personally believe it will help.