You mentioned the B-25 being best for the light armored vehicle, while this may be true, it fulfills all roles except fighter (unless done right) rather well. I have killed all vehicles with the cannon and all but the Tiger and 251 (little bugger is rare to see) have gone down in one hit. So really unless you are careless with the plane it is great for all those spots. Simply aim for the back/side of the turret or the gas tank and get a one hit kill. If you need to kills flaks and for some reason can't get it with cannon/MG then just bomb it, ya got 6x 500LBers, or 3x 1,000LBers (or whatever variation you take). Also PT boats are not a smart idea if you get overconfident and think it's going to be an easy kill, that thing is armed more than enough to kill a B25 in one pass.