gold star for USAHOF
One of the most popular players in Seattle SuperSonics history, “The X-Man”, Xavier McDaniel was an All Star in 1998 and would average over 20 Points per Game with Seattle.  The beloved forward would help the Sonics go deep into the playoffs multiple times, even when he was used in a bench role.  McDaniel would post decent numbers as an offensive rebounder, a trait that would make him popular everywhere he went.
You hear a lot about "glue guys" in the NBA and the players that may not be statistical beasts but have an intangible that makes a team want to keep them.  Such a player was Nick Collison, who was a star at the University of Kansas but was a bench player with the Seattle SuperSonics/Oklahoma City Thunder for all fourteen (2004-05 to 2017-18) seasons in the NBA.  Collison rotated between Power Forward and Center, where he helped them reach the 2012 Finals and always provided leadership and stability.  While his overall averages of 20.2 Minutes, 5.9 Points and 5.2 Rebounds per Game may not seem impressive, there is a reason why his #4 was the first jersey retired after the team relocated to Oklahoma City.
Seattle is a beautiful city, but for Dale Ellis it had to be a paradise after being traded there.
The son of Hall of Famer, Rick Barry, Brent Barry was one of the most accurate shooters during his time in Seattle.  Known for his three pointer, Barry would never shoot below .400 from behind the arc, including one season (2000-01) where he led the NBA.  Barry would also lead the Association twice in Effective Field Goal Percentage and once in True Shooting Percentage. 
A defensive minded Guard, Nate McMillan played all twelve of his seasons in the National Basketball Association with the SuperSonics.  Five seasons, McMillan would average over 2 Steals per Game, including a 3.0 run in 1993/94 that would lead the league.  Twice he would make Second Team Defensive honors.  While McMillan was not known for his offense, he was a decent distributor and had solid Assists numbers throughout his career.
Spencer Haywood challenged the rules of the National Basketball Association by declaring himself eligible for the draft after his sophomore season in college.  The NBA refused to allow him to play (as the rule at the time was that a player was not NBA eligible until the college class graduated) so he went to the upstart American Basketball Association and promptly won the league MVP as a rookie.  As you can imagine, somebody from the NBA would covet a talent like this, which was occurred when Seattle signed him anyway and a lawsuit went all the way to Supreme Court.  The NBA settled and the Sonics had a star.
Inducted into the Naismith Basketball Hall of Fame as both a player and a coach, Lenny Wilkens was a player for Seattle for four seasons going to the All Star Game in three of them. 
In every full season that Ray Allen spent with Seattle, he was named an All-Star.  Known for his sweet shooting skill, Allen’s season average never dipped below 23 Points per Game (as a Sonic) and without question, he was considered the king of the three-point shot.  Allen would later become part of a “big three” with Paul Pierce and Kevin Garnett and win a Championship in Boston but guaranteed there were many in Seattle cheering him on in his later accomplishments.
The first German star of the National Basketball Association, Detlef Schrempf was already an All-Star (with Indiana) when he came to Seattle but it was in the state of Washington where he would become a national star.  Schrempf was a part of the Sonics' push to the 1996 Finals and would make two more All-Star Games while playing for Seattle.  Schrempf would post his best scoring season with 19.2 PPG (1994-95) as a Sonic.
Signing with Seattle as a Free Agent, Gus Williams became a top scorer in the NBA.  Williams would watch his numbers climb in the first three years and would have likely saw an increase in the fourth season had he not sat out the entire campaign due to a contract dispute.
Drafted later than most pundits thought he would be (he was 32nd overall and the last waiting in the “green room”, Rashard Lewis would blossom into stardom with the SuperSonics.  In the 2004-05 season, Lewis would make his first of two All Star Games (his second would be with the Orlando Magic) and rattle off three straight 20 Point per Game seasons.  He remains one of the most prolific three point shooter in Sonics/Thunder history.
Known for his sweet outside shot, “Downtown” Freddie Brown was a productive Shooting Guard for thirteen seasons, all of which were with the Seattle SuperSonics.  Brown would be one of the first true beneficiaries of the three point line as he was the first leader of three point percentage when the rule was instituted in the 1979-80 season.  The season before, Brown (though coming off of the bench) captained the Sonics to their only NBA Title.  He would average over 20 Points per Game twice and represented Seattle in the 1976 All Star Game.
Dubbed the “Reign Man” by the Seattle faithful, Shawn Kemp was best known for his many kids with multiple women as he was for his on the court skill. 
With your Center, you hope that he can give you a double-double on a somewhat regular basis.  Sikma averaged that seven times as a SuperSonic all of which saw him go to the All Star Game.
One more season in Oklahoma would have probably put Kevin Durant in the number one spot for the Sonics/Thunder list. 
When you are nicknamed the “Glove” it is expected that you are one of the greatest defensive players of all time.  This is exactly what you get with Gary Payton. 
Russell Westbrook is one of the best scorers in the game…period.