Don't forget that you can pass the ball from the pit up a level or two if you position the AoE targeting reticule just right. This is a GREAT way for anyone to use the pit to their advantage considering the enemy team almost always follows the ball carrier down into the pit.
The only downside is that if you jump into the pit a lot of friendlies will jump down to follow you without thinking. :\
If you jump down on the pit the opposing team has to follow in case you pass it to someone who has a force leap ability, because then you can use the guy up there to jump back up and that gives you pretty much the best position possible (pass all the fire traps).
The defense strategy should be to immediately KB anyone who is still above the pit when the enemy takes the ball down there, and then immediately jump down to prevent force leap tactics. If you can't get rid of people above, then you've no choice but to kill them first and then jump down.