For Marcus to average 9+ points considering all of the factors he currently has working against him bodes well for him...
I said this with Avery and I'll repeat it with Marcus, one factor affecting his offense is that the amount of energy he expends on defense, negatively affects his offense. Players cede defensive effort to increase/maintain offensive effectiveness. It's the reason why players like Lebron, George, Butler, etc. appear to have slipped defensively... They choose to dial it back in exchange for energy on the offensive end.
Another factor is the disrespect Marcus is receiving from the ref syndicate... A crucial part of Smart's game is drawing contact and getting to the line; it almost looks as if he's being targeted for no-calls.
Lack of confidence in his driving/finishing ability, his shot needing to be reworked, and him identifying and implementing a go-to move are the other factors. Considering all of these factors, it should be no surprise that he's inefficient.
Back to the topic, Smart has shown excellent court vision throughout his young career. I think that he will eventually become the floor general version of him that we saw in summer league. Something like 15/7/5 with excellent defense.