Hmm, the only bit I have found even moderately useful is the national unity breakdown, where it shows the values for how much negative effect you are getting from being strat bombed and losing convoys, and then how much offsetting positive NU effect you are getting from intercepting bombers and sinking raiders, respectively. I haven't seen reliable data on how much economic damage bombers are inflicting, either yours or the enemy's. As you rightly point out the strategic data window, though a good idea, was never implemented properly. More's the pity.