I made an European scenario that isn’t very balanced, but fun, against the computers modeling the early 20th century diplomatic situations (and, obviously, the wars.) I made everyone have essentially unlimited resources, because I figure that most problems with production in that game are speed bottlenecks, and bombing factories would do that.
It may be more balanced if I made the computers harder, but I hate invading Russia when they actually fight back…
P.S. You play as Germany, because Tiger tanks are very powerful, and they are a great civilization to play as anyway.