Something really interesting also:
Expanded ground ops let you take advantage of distinct terrain types (desert, forest, urban, swamps etc.) for mobility, weapon effects and visibility. Enhanced AI routines for dogfights and even more technical factors make your grip on air superiority more tenuous. The groundbreaking features of the “Chains Of War” campaign are now standard: Disrupt your enemy’s communications to isolate his units (but watch out for your own), perform scriptless amphibious, airdrop or pickup operations, watch as aircraft limber back shot almost to pieces and marvel at exotic new weaponry.
People matter - now even more: Even at the dawn of unmanned systems, combat is not a dry hardware comparison. Your war machines are crewed or remote-controlled by human beings: people trained with varied proficiency (from novice to ace), operating under custom doctrine and rules of engagement (when to do what, how to decide, how to react etc.), most of the time making the rational decision, and sometimes making a brilliant call or a mistake. These people often matter far more than the hardware. The deadliest combat units are only as sharp as their crews.
* Any WW2 scenario in the works? There are far greater ambitions for WW2 than merely a few scenarios, so stay tuned!