Yep. People talk about "nutcase" and "terrorist" like they're independent, mutually exclusive possibilities. But they're not. The shooter/s or shooter team could be some of both.
"Mercenary" and "professional" could be part of the mix, too. AQ or another organized player could have contracted with someone. Or manipulated them into doing it.
The shooter team is so good at not leaving evidence and knowing where police look and don't look one has to wonder if there's a law enforcement background in there too.
My own suspicion is that the shooter is not leaving the shooting scene in a car or truck. They might be staying in the area in a safe place until things quiet down or even using public transportation. I haven't heard that the police are stopping buses and searching the passengers.
Depending on how bus coverage works near Tuesday's shooting, the shooter maybe could have walked somewhere close by and caught another bus. Would be an ironic touch after they just shot a bus driver (prayers for his family and may his soul rest in peace).
But there's a lot we don't know.