One one side, people should think twice before they dump an A300 or larger aircraft on a route. It requires common sence, which as ive noticed is a scarce commodity here in AM, to tactfully and effectivly draw your routes. I think common sence means deciding not to put an A300 on a route, even though you stand to profit from it. Ive noticed alot of my routes have a pretty good balance on them, they found equilibrim long ago and have since been extremly profitable, i havent needed to touch them in weeks. If i put an A300 on them, i might make 10k more than before, but in doing so i would disrupt that equilibrim and challenge those folks into acting in kind which would threaten the value of that route. Certain routes are fine, others are a bad idea for various reasons.
To blame is mainly the mathematics of AM, i really dont understand the passenger to value caluclations, but they tend to be rediculous the more people are on a route. Case in point the 1€to loadfactor issue. In real life it could be profitable to run an A300 FRA-DUS on a frequency of 9. but in this game its idiotic, yet some people do it for one reason or another. Some people have yet to meet my friend here 'diminishing returns'.
All in all i find that only about half the canidate routes for an A300 would actualy be good for that aircraft. Ya just got to have the forsight and do the reasearch and make the executive decisions to carefully pick and chose which ones, and which others might do best with a caravelle or 737.
On the otherhand i can understand that you need to make money too, thats why your here, and this aint a charity. This is capitalist theory at its quirky best. So by all means go forth and do whats best for number 1. It dosent supprise me that people will take it personaly sometimes I do, even though theres no reason to. I suppose its the lack of communication in the game thats most frusterating. But all in all you have no fault. if your really making money with those birds, and are making more than before than i suppose you made the right call to buy em and use em.