Get a return ticket for the 727 Shuttle Bus direct to Aberdeen City Centre. Costs a fraction of the price of a taxi. The shuttle bus also has free wi-fi.
Security queue times are a crapshoot - if it's not busy, you sail through in 1-2 minutes. If an international flight is scheduled for departure though, that's when it takes forever.
...and let's not forget that despite all the so-called investment in the airport, passengers still have to queue outside to board the plane come wind, rain, snow or hail.
I have seen the airport change from a local airstrip in 2005 to a international airport to be this year, ever time (16 times by now) a step better, keep on developing.
The airport which makes Aberdonians embarrassed. Badly run, often rude staff who enforce ridiculous rules which even the experienced traveller has never encountered anywhere else in the world.
ComCab taxis operate from door. Others can be summoned to pick up. Bus service into town or to Dyce rail station. Allow time for heavy traffic at rush hours.