I think your being unfair there
Jaez.
Belfast accents vary greatly. I have found that a good way to imitate a Belfast accent is to breath through your nose as you speak.
Try: "Wise up there wee lad" as your breath through your nose. Its quite amazing how this adds to the Belfast accent.
As you leave Belfast and go to surrounding areas you get different accents. A running joke in Northern Ireland is,
Q: What is a Creche?
A: When two cars collide on the Malone Road