You're welcome.
Well, let's see -
1) No crappy gimmicks whatsoever.
No Crib, no fake sega characters that have nothing to do with being in a football game whatsoever. When I first played 2k4, I unlocked some guy named Taka or something like that. He was an OL. His pic was like a cartoon. I laughed my *** off and was then pissed off that this fictional player was now in my franchise mode. By the time I found out that changing your user name to "none" before every game eliminates the Crib 100%, I had already sold it and went back to 2k3.
No "goals". This was so stupid. Your team had goals (like 2k5) that it had to meet. Sorry, but winning the SB is the only goal I care about. Not all this other crap. The funny thing was that if your team did bad - your head coach was fired (like 2k5). Of course, what really happens is that you the player gets fired and cant play any more games in franchise (unless you start a new one of course) but yet, can simulate season after season, game after game until you fall down and die. So damn stupid.
I'm not sure if there were any more other crappy *** gimmicks but if I remember any, I'll post them.
2) Play-calling menu.
I dont give a damn what anyone says. The original, unique and innovative playcalling that was in 2k to 2k3 blows away the crappy old, small, player's routes are cut off, obsolete, if I wanted this I would play Madden, boxes.
3) The three circles that are on the field when you pass.
While most probably dont know what im talking about, there were three circles that appeared on the field when you passed. The middle one was the biggest while the two outside ones were smaller. The reason they were there was for catching the ball. The middle circle allows you to catch the ball in stride and continue running. The first circle allows you to jump or dive for the ball while the third circle makes your player turn around to bend over and try to catch the ball before it hits the ground. This made catching fun for those like me who switch to the receiver after I pass the ball in order to catch the ball myself. This little "+" (plus) sign that appears when you pass in 2k4 and 2k5 is garbage. It's nearly impossible to catch lobs unless your perfectly on the marker. Half the time, my player "bounces" away instead of jumping or diving for the ball.
4) The controls.
While im used to the control setup in 2k5, I prefer 2k3's setup over 2k4/2k5. The majority is the same but in 2k3, the Triangle button was to hurdle while pressing the L1 and R1 buttons performed a shoulder charge. This felt a lot better and trust me, running over a LB with a 96 rated Ricky Williams was a lot more fun then it is in 2k4/2k5 (at least to me anyway). On defense, the Triangle button was used to intercept passes. In 2k4 and 2k5, its either the stupid L1 or the Black button. Horrible. And I used the PS2 setup as an example since that's what I had 2k3 for.
5) The gameplay.
The biggest problem was the in-ability to sack the QB. Like the other poster said, you would have to hit the QB with one guy and after he gets shrugged off, sack the QB with the second guy. In 2k4 and 2k5, its the opposite. It's way to easy to get sacks so it evens out.
The reasons why I enjoyed 2k3's gameplay more then 2k4/2k5 was not only because of the three reasons above but the running game was so far superior then either 2k4 or 2k5. In 2k3, in order to perform a "good fast" spin move, you must time the move. It's all about timing. When your RB is ready to make contact with a defender, performing a spin move makes you RB spin off the defender real fast but if the timing of contact is off, you'll have a slow crappy spin move where you are then open to being tackled. In 2k4/2k5, you can spin at any time. I hate that. No player with the ball is going to spin just for the hell of it. Players only spin when they are about to make contact with a defender in order for the defender's arms to slip off the ball carrier which thus lets the ball carrier get away for hopefully more yards. To me, its just more realistic. The stiff arms were useless at least for me anyway but the spin move being better made up for it.
That's all I can think of right now. I own 2k4 (and 2k5) for Xbox but havent played 2k4 since I purchased it three years ago on PS2. I would say why I still own 2k4 for Xbox but doing so would spoil one of the many things that im currently planning to do with my 2k7 roster update.