You can also consider Olivenhain (I can never remember how to pronounce) which is part of Encinitas. I think you can find two acre lots, with large square footage, but slightly more convenient access to shopping and errands.

As far as malls, you have UTC down in UTC or where I live my wife will typically go up to Carlsbad Outlets, or the Carlsbad/Oceanside mall along 78 and El Camino Real.

From RSF there might be a mall in RB that is closer than Carlsbad.