For all the rivalries such as Pistons vs. Heat, if you want to be the Heat, go to manage the team rosters and make everyone's height on the Pistons 4'6". Then, change everyone on the Heat to 7'6". This way, you will be able to shoot easily and don't even have to save the roster. Make sure that you set the difficulty to Hall of Fame before beginning the game or it will not count. Do this for all the rivalries for lots of Gamerscore points. If you want even more Gamerscore points, you can trade players such as Yao Ming or anyone you need to get certain stats with, to a team that you need to win a rivalry. By doing this, you can get two achievements or more in one game.
-Use the following trick to get easy player achievements such as 81 points with Kobe Bryant. Begin the game with the player's team, then pause game play. Go to the screen with your settings and turn your attributes all the way up, then turn player lock on the person you need to be. Next, turn the foul bars all the way down (reaching is the biggest). After this, you can make almost half court swishes and easy dunks. When the opponent gets the ball back after you score, wait by the man they will pass to and simply steal the ball when he has it. You can be reckless because there are no fouls. You can even do rivalries at the same time and get the Magic Johnson ones as well.