> It might be a disadvantage to take off uphill, but I believe that it's desirable to take off into a head wind.

Both takeoff and landing are safer and more efficient in headwind, since lift is a function of airspeed an increase in airspeed (from headwinds) a larger margin or security or lower groundspeed in both situations.

GP's point is if your runways are slanted (rather than flat), instead of having both takeoff and landing use the same runway in the same direction (headwinds) you now need a runway slanting into the headwind (for takeoffs) and one slanting away from it (for landings).