The traffic around ABZ (Dyce) is shocking between 7am to 9.30am and 4pm to 6pm Monday to Friday. Avoid these time periods if you've a flight to catch.
The A96 from Inverness to Aberdeen is a dreadful road - full of HGV's and limited passing opportunities and boring in terms of scenery.
Take the A9 south to Carrbridge, cut across to Grantown on Spey, then take the A939 over the Lecht to Balmoral and then onto Aberdeen via Dinnet, Tarland and the B9119