Better aerodynamics trump weight (within reason - and your case is definitely within reason).
The fairings on this motorcycle...
... added
88 lbs to the stock motorcycle, which only weighed 231 lbs to begin with ...
The stock bike can get 114 mpg (US). The faired (and re-geared) one can get over 200 mpg (US), despite the 88 extra pounds.
This is an extreme example, but unless you're only operating at very low speeds in stop & go type driving, aero mods win.
214 mpg with DIY aerodynamic fairings on a Honda 125cc motorbike | Hypermiling, Fuel Economy, and EcoModding News - EcoModder.com