I've watched the NBA for about the last 23 or so years. I am a highlight junkie who loves the old school games and players. Guys like Isiah. Karl Malone...old school, hard-nosed veterans. The league has changed dramatically under the control of David Stern throughout the years. Mostly for the better.
From his stoppage of imminent brawls through his punishments, to him upholding all players to the same standard. People often criticize him for upholding the suspensions of Boris Diaw and Amare Stoudamire during the Phoenix-San Antonion series in the playoffs a few years ago. I respected him for standing his ground.
After all, I remember Patrick Ewing and Larry Johnson getting suspended in a playoff game against the Heat. They took one step on the court. Amare and Diaw made it all the way to the scorers table. Why should they be different? Everyone, and I mean everyone should suffer the same consequences.
Stern's ear is also open to listen to his players. When he changed the regulation game ball, he was flexible enough to change it back when heard of its disapproval amongst his players.
So many changes have affected the league in a major way. The NBA is a financial juggernaut through products, media, endorsements, and charity. I had to list three negatives to even the list out, since there were a few changes I disliked. But with the exception of one, they've all been very miniscule.