3. Michael Finley
Michael Finley played from 1995 to 2010, including a season and a half with the Suns to start his career. While Finley was traded for Jason Kidd, an actual hall-of-famer, I still think Finley is worth putting on this list given his consistent production for most of his career.
He was an immediate impact player for the Suns, starting 72 games and averaging 15 points a game as a rookie. He would go on to be a two-time all-star and an NBA champion with the Spurs in 2007.
If Jason Kidd had stuck around with the Suns for longer, Finley might not be on this list, but considering after a few years, Kidd was swapped for Stephon Marbury, trading away Finley looks a lot worse in hindsight. It made one trade that seemed good on paper essentially get canceled out by a bad trade.
Now a Mavs legend and hall-of-fame candidate for the past few years, Michael Finley could have had just as good, if not better of a career if the Suns had kept him. Maybe they could have swapped someone else with Finley with the trade for Kidd. We will never know, but in hindsight, trading away a 15-points-per-game scorer in his second season was a bad idea.