Its possible.
You have to go to tasklist.dbf in the saves folder. You can edit the points required for doing some tasks and the points rewarded for all tasks. But, for some strange reason, after doing that, open NBA LIVE 2005, open your season/dynasty and EXIT WINDOWS. Then reopen NBA LIVE 2005 and your season/dynasty and in the task list now you can see the points edited.
For example, I use it because i am in a custom dynasty with 29 games (and I play full games). Is impossible to score 8200 points in a 29 games season, so I edit it to 2900 points. And the champ is 500 points (the same as the ones like "advance past 1/2/3 round of playoffs) but I think it is more important, so I put 2000 points.
Hope this helps.