Well...if you do choose to keep the nose high and aerodynamically "brake" the plane, you must know that plane well. From memories of the A300 (beautiful plane which I loved) there was a "flight idle" still giving good thrust on our General Electric CF6s and a "ground idle" with much lower N1. And that ground idle was obtained...when the nosewheels were on the ground...(I am going to check, but I am pretty sure of it). Nose wheel high...aerodynamic braking...with a lot of thrust on both engines...not ideal certainly?