Is there a mode that lets me set P and A?

Another method based on an exposure method that a number of people have recommended for general use is to set base ISO on the camera, and in manual mode choose the shutter and aperture you want (ignoring the exposure scale).  Shoot in raw and then adjust exposure in PP.  Supposedly, because of the new sensors, the resulting image is better (less noise) than it would be setting a higher than base ISO.

I haven't tried this, and because of biases from my film experience, I question if it is as fool proof as advertised.  But it's probably worth experimenting with to address the OP's issue.

Tom