To me, Axis & Allies is WW2 in afternoon. The additional play interest and historicity of every rule needs to be balanced against complexity and time burden.
I have find that the political rules in the Global game, add substantial complexity with adding much to interest of historicity. It would have been better to have political events occuring at specific turns.
The recent North Africa game was also burdened by too many rules. All though, the individual mechanisms were interesting & historical, overall there was too much going on, too many little things to keep track of.