Even if basics of uncontested flight seem fairly easy compared to more advanced sims, already had insights of a few of it's challenges as well.
These include:
- combat maneuvers & shooting, especially at great speeds,
- limited ammo management & memorization,
- challenges of 'a risky flights', especially with a flight closer to the terrain obstacles,
- turn & speedup maneuvers, in all directions - including up & down,
- terrain awareness & memorization,
- squad wings awareness, wing tactics & combat as well,
- ambushes, bases, ground forces involvement, they can move as well,
- a time pressures,
- probably much more as well.

More than a two of helicopters at once.
(click to enlarge if You wish.