Maybe I'm missing something but why not just open the hatch, get the snow brush, and then start the car? I'm guessing you're trying to use the remote start beforehand and stay inside where it's warm and then brush the car off?

In that case I guess you'd have to stop the engine, open the hatch, get snow brush, and then restart the engine?

Or

You could keep the snow brush in reach of the driver's side door so you could use the remote start fob to open the driver's door and get the brush that way without turning the engine off.

I only bought my Soul (used think it's a + model) in August, and this is my first winter so...guess I'll figure it out but your post helps me strategize.