only pick the missions that pay more then 500 000 cr / ton.
I don't choose the missions based on pay out alone. I try to find them for at least $3Million, then I check the delivery point. If it's an outpost or a planetary station, I grab it if it's within 1000LS of the main star. If it's a delivery to a full size station I try and make sure it's a $4Million payout so that it's worth the extra risk.
I also try and grab at least one of the high-capacity, don't-fail-if-scanned regular missions so that there is an opportunity to make Credits even if I get scanned. I usually end up with 5-6 shadow deliveries, with one or two at full sized stations, and one higher capacity mission. I get a mostly full cargo hold so I can try and reduce the trip length by 1 jump using the slider.
I just tried, and had no problem filling an 88ton ASP, which I think was just under 20 missions. Let's say 15 then. Let's assume you're low trading rank, so 2.5m Cr per mission. That's just shy of Cr 40m for a single run. And you can repeat these indefinitely once you learn how to avoid police/pirates.
I get why people would want this to be fair, but come on, you me and everyone else who bothers to think this through realizes that this is dependent on the glitch which is "relogging-for-new-missions" to be viable. But I might be completely wrong, and it might of course be FD's plan to accelerate all players to Anaconda and beyond in a week. But do you really think so?
I know how to avoid the police/pirates. Knowing how doesn't translate to a successful run 100% of the time though. I've made mistakes flying absent-minded and failed tens of millions worth of missions. Knowing is half the battle, sure. But you still have to execute, which is not guaranteed.
If you are very selective, you can find shadow missions with 3-4 cargo each. Rip the shield out of your Asp and fill it with 1 class 5 Fuel scoop + lots of cargo racks. With 96t of cargo space, you could gather a lot of missions, if you really want it.
Edit: Delivering so many missions at once would be too boring. I tried it with 30+ courier missions an canceled half of them at the end.
Yeah, I'm not flying with out shields. I guess I'm not that good. I don't know how many times pirates/security dropping into the same instance after an interdiction have ruined my shields and dropped my hull down further than I as comfortable, or pirates following me to the landing pad at an outpost, hitting me with cannons the entire time. Not to mention boosting into stations to avoid scans.
And I don't really want to stack that many missions. Stacking 7 is pesky enough with the number of interdictions and scans you face. I've tried more and it was, IMO, more trouble than it was worth.