I don't care for the speaker in the front either. Both because of appearance, and the sound will all be coming from the left.
(I know donkey kong was like that, but the speaker was at your waist, away from your ears)
If the cab is on feet of any kind, consider having it underneath the cab pointing down.
The one in my megatouch is pointed down and sounds pretty good.
Since the speaker won't be pointed at you, it won't be as directional.
Are you centering the joystick or putting it to the left?