As announced, here are some key stats on the (formation) bombers in 2012
First, the standard historical "usage" chart. I just didn't name it that way this time, because as explained earlier the method of adding Kills & Deaths doesn't really work with a category of planes in which many types do nothing but to avoid any hostile contacts due to limited armament and/or very high perk price.
So take the following chart just as giving you a very vague trend, but not a real indicator of relative usage:
The next one shows the causes of combat losses for each formation capable bomber type in AH. Of course I can't track AI ack or operator errors (taking off towards a steep hillside...)
As you can see, the causes of deaths vary a lot between the different types according to their main mission profiles. A high share in deaths by ship/field gun is mostly a result of many naval attack sorties.
The following chart depicts the A2A K/D of each level bomber. It doesn't show overall survivability (this depends a lot on speed and mission profile as well), but shows how much (or little) of a fight a bomber can put up when actually caught by a fighter.
I would love to correlate that with number of sorties flown, but sadly HTC doesn't make this information available.
And at last (for now), a look at the top 10 B-29 killers of 2012 by number of kills and the K/D against the Superfortress: