Career stats through first two seasons:
Player A: 8.5 points, 2.5 assists, 2.6 rebounds, 0.9 steals, .370 / .298 / .793, in 23.8 minutes
Player B: 7.0 points, 2.8 assists, 1.8 rebounds, 0.8 steals, .371 / .301 / .725, in 19.8 minutes
Player C: 6.5 points, 2.2 assists, 1.8 rebounds, 0.6 steals, .344 / .333 / .748, in 19.5 minutes
Player D: 7.9 points, 3.0 assists, 3.3 rebounds, 1.5 steals, .357 / .313 / .657, in 26.8 minutes
Player E: 5.3 points, 2.3 assists, 1.6 rebounds, 0.6 steals, .368 / .376 / .815, in 17.1 minutes
Who are the above?
Marcus Smart must be player D. The steals and rebounds give it away. But those other lines are pretty similar in other respects. What kind of players are we dealing with here?
Player A: Erick Strickland, 1997-1998 Dallas
Player B: Mike James, 2002-2003 Miami
Player C: J.R. Bremer, 2003-2004 Boston, Cleveland, and Golden State
Player E: Steve Blake, 2004-2005 Washington
Best case scenario from that group is Mike James. He overcame the rough start to his career to become a deadly shooter. Even averaged 20 points per game once.
These are the best comparisons I could find at Basketball-Reference looking for guards with similar averages to Marcus, including field goal percentage well below 40%, for the first two years of their career.
Of course, Marcus still has a ways to go before he's done with his second season. I really hope he does some good things with the next few months.