Hello all,
I've been playing Legacy Mode pretty steadily for the last several weeks, and I've noticed a few things that could use changing:
1) Timing of "Events": It makes no sense that the popularity events take place during your four week training period. What manager in their right mind would allow their fighter to miss 25% of their training time to go fool around with giant boxing gloves for Nike? Also, why in the world do you lose an ENTIRE week for doing one radio show?
2) Champ inviting you to spar: So far, every time the champ has invited me to spar, the event has been placed in the last week before my next fight. Meaning I have the choice of either * off the champ or trying to win a fight starting at 50% stamina.
3) Sudden drops in boxer rating after fights: If I have a boxer rated at 94 or 95 going into a fight, and then I win that fight in two or three rounds with no damage, it makes no sense for my boxer to slip back to the low 80s going into training for the next fight. I didn't expend enough energy to be exhausted, certainly not for weeks, and I wasn't injured needing recovery.
4) Unrealistic CPU opponents: My current legacy boxer has knocked out Ali twice and Tyson in FOUR separate fights. Those two are the highest rated heavyweights in the roster. So how is that this same boxer, rated in the mid-90s before a fight, can get pulverized by a boxer ranked in the mid-80s with lower stats in every...single...category? If this fictional CPU boxer is supposed to be on par with Ali and Tyson, then rate him that way so that a boxer comparison will show what's coming. And note, I'm not talking about some out-of-the-blue knockout punch, I'm talking about overwhelming power punches with no loss of stamina and defense much better than the ratings for reflexes, blocking, and head movement would indicate.
5) Stamina: Really? I mean...really? The CPU boxer always gets 10-13% of his stamina back, even with low ratings for stamina and conditioning. But my boxer goes in with 100 ratings in BOTH, and I fight conservatively with lots of movement, and get at best 10% back. Usually more like 7%.
6) Damage: The only damage that really stays with a boxer, round-to-round, is from body shots. Do body shots, and the opponent comes into the next round with less on his health bar, closer to a stun or a knockdown. But do head shots, up to and including cutting both eyes, breaking the nose, and splitting the lip, and that injured boxer comes into the round no closer to a knockout.
7) Sparring: on more than one occasion I've gone into sparring to find the same boxer I'm about to fight as my sparring partner. That makes NO sense. At all.

Limited number of opponents in late stages of the game: I'm currently at "Super Star" level, with all three belts, and the only available opponents are the same five guys. One of whom, Ali, keeps "retiring" only to pop back up on the list. You should be able to invite one of those "boxer of the year" winners to take a shot at the title.
These are just my thoughts. I've enjoyed the game a lot, the graphics are fantastic and the gameplay mechanics are sound. Still, as with anything in life, there is room for improvement.