Here is another thought.
All this talk about RB-17 happens when Attrition mode is happening. Attrition mode is a little better than Invasion mode, but it is still very imbalanced compared to standard 2.0.
In Attrition mod the most effective planes are fighters. Then ground attack and bombers. There were games when all the map is red, but my team still wins, because if enemy teams don't kill planes (defenders don't count) no matter x3 or x5.
The thing is in Attrition mode there is no point of flying multiroles and heavies. Heavies can't kill fighters fast enough. Multiroles cant damage enough ground targets and also less maneuverable than light fighters. Bots are much smarter, in much denser groups, have better ammo, much faster and fly from the bases farther. They (mutiroles and heavies) can't affect the win much. Multiroles and heavies are the main enemy of bombers and ground attack, and nobody cares to kill them - because it's gonna take them too long time. And it's better to kill 2 fighters than one bomber/ground attack - more points, even if the other team has more bases.