+1 for offline mission AI improvement.
The AI actually used to be much better and much more challenging than it is now. However, I cannot think of a time when offline missions were not buggy.
It seems to me that HiTech kind of ignored the offline missions in order to focus on the online arenas and the aircraft, which is understandable from a business point of view. However, it would be much appreciated if they fixed up the offline mission system once and for all.