Yeah...... well, I think that the roles of spy and assassin should have been combined. For example, I cannot for the life of me see why a spy cannot perform a building sabotage, or why an assassin cannot scout out the surroundings. And generals should have an inbuilt ability to negotiate alliances. Sure, that reduces the relevance of diplomats, but it doesn't make it redundant, as generals generally (ooh, alliteration xD) have more important things to do than running around the map.