1 - Disconnection is server's fault. Period. Everybody is facing this issue, nothing can be done by ourselves.
2 - When your bullets seems not effective against some reds, that's caused by your target's lag. As an example, I have a really bad 3G connection in this new town I chosen to live, and have seen lots of complainings; some moderators already quicked me from some games because of my end's lag.
There is something that can be done to minimize this issue: when you are sure you hit your target twice (or three times on his/her wings), let him/her aside and go for your next target - the laggy target will be down by your bullets some seconds after you hit him/her.
And please, understand that, although lagging is an annoyance, one should not be simply BANNED by the mods just because he/she is lagging. It isn't fair, as laggin isn't player's fault.
Surely, when I see that I am messing with the game at a point that other players are being really annoyed, sometimes I quit, to give them peace - but I don't do it as often, because I have the right to play this game too.
The only efective - and fair - workaround would be the implementation of some kind of "automatic filter", running full time on the servers, preventing people with bad connections to even log in. But while this tool isn't implemented, all of us laggy players have the right to play.
That's my humble opinion, of course, because as I already said, some mods are not too acquiescent, and quick me every time they see my plane lagging.