Wow, I thought I knew the games in depth. '01 & '03 are essentially the same with a few differences. I'd choose Stephanie a lot more often in '97 because she is better in nearly every way, and that sentiment is fairly true for most kids. What we talk about is generally correct (Achmed is still an awesome power hitter, and Amir plays better with him), but specifics are definitely different.

In '97 if a player was having a bad or good day you couldn't see what ratings changed, in '01/'03 you can see what their exact ratings were on a given day Season games are not all played on the same field IIRC you don't get batting powerups in '97 for turning a double play

Kenny & Pablo are no longer top pitchers, Jorge somehow learned to hit with that swing, Ricky can't hit at all with his. Stats changed when going from a 4/4 to a 10/10 system. And I'm not just talking about bouncing it, they can't even roll it that far. Some players in '01/'03 can't even reach base to base. In '97 a lot of errors are cause by throwing while it is much rarer in '01/'03 as the throwing power is much weaker. Most notably throwing is much stronger in '97. All is IIRC (tell me if I miss something). I'm going to omit most things about pros and secondary things like standing structure in season play. It is the same basic game but with some distinct differences. The original (hereafter referred to as '97) is different.

Players in backyard baseball 2003