I liked Marta a lot, and I liked Aaron, but I just felt the story could have done with being less crazy car chase and a little more fear of going back/flowers for Algernon.

I suspect you're probably right (as long as we don't have to give up Marta's final kick, of course) - there was definitely way less focus on Aaron's past/participation in the program/etc. than there could have been, and a lot more motorcycles. I feel like the pacing ended up a bit strange because the viraling-out was relatively straightforward: they knew where they had to go, it wasn't especially hard for them to get there, &c. If that had been a little complicated, I think they might have had more time to get into Aaron's head.

Of course if I was in charge we would have at least an hour of sweaty half-naked Aaron fighting the superflu h/c deliciousness, so maybe it's a good thing I am not, in fact, in charge of the film industry!

I'm the wrong person to judge, because I would totally watch that. :D