Just a remark on general skill level and effort: Even if all players would start to show much more effort to "get better", the median values wouldn't me not that much different in my opinion - because no matter what, there will always be a minority of players being much better than the majority. And in a combat game like AH, the majority of players are mostly the victims of a minority. (And this is exactly why it is so very important to have other means of 'winning' than just shooting the enemy down, by capturing bases and winning the war)
If we look at the kill balance, that is all kills of a player - all his deaths, only about 25% of all players have a positive result - only one quarter kills more than being killed. Those 25% feast on the other 75%.
And Butcher - you are still calling "average" what clearly isn't average. Someone with K/D of 7+, and similar levels in the other kill stats, is not "average" veteran, when the average veteran (those guys right in the middle of the rankings) is struggling to get his K/D to 1.0.
You may rate yourself not as a very good pilot on the raw skill scale (from 0 to perfect), but compared to the utter majority of long time players, you are still way beyond them. They just suck more than you.
I know that feeling quite well: I don't realyl think of me as a very good fighter pilot, because I know there are like 100 players that can consistently kick me around at will. Oh my god, I suck! But then that also means at the same time that there are like 3900 who can't

I can only emphasize again: The skill level of the mass of AH players is frequently overrated. Because they are anonymous, we only see and talk about the very small number of top pilots (maybe 50 or so) and their heroic feats, not the ~4000 or so ordinary guys making up the arena.