I have 4 routes on my sole A300 with a total DOP of €305,794
I have 3 routes on my sole 742 with a total DOP of €333,090
I was hoping to get around an average of 130-150k on each route, but the most om getting is 110k and 80k
do the math 
Isn't the 742 around 3x more expensive?
do the math 
:oops:
but still, my leased 732adv is making more money than the A300, and thats with it having much less seats than the A300.
If the A300 has 300 seats, then it should give a higher DOP
Not really true, like I had mentioned earlier, eventually, you'll put so much capacity on a route, that it gets to a point where it simply becomes more logical to put a smaller aircraft on routes. Like for example, if I were to fly Vnukovo to Kiev Zhilny, I'd find it a whole lot more desirable to fly a Yak 40 or L-410 than use a Tu-154 or IL-62. I should share a experiance I had flying my first round in the 2000s era. I tried to start Kalingrad to Pyonyang services, the first plane I put on it was a 777, I was losing around 10K a day on it, so I had to try putting one of my A310s on it, still losing a good 5K on it. After that, I leased out a G500 and guess what? I was making 5K on it (if we had BBJs then, or something of that equivilant, which can hold about 50 people, I'd probebly be making more like 10 or 15K.) Granted, my example used two smaller airports, but what I had explained can still hold true, not every plane will fit on every route, no matter how many seats it has.