I thought someone did some tests on bêta to make up the listIt's not on Beta. It's on this thread. Even if it wasn't, anyone can sit and figure out which chests/beacons give the best return for winning artefacts. They tell you all the probabilities. With a questline that's so quick and simple I don't think it's much of a hardship to say that people will need to think about their strategy a little if they want to win a certain thing. Not everyone even wants the artefacts so many people will be choosing what is best for them if they'd rather win dailies. If you've been constantly picking the 83 or 92 beacons then no, you will never get to 9 artefacts.
And yes exactly, according to what you want you want you should be able to find in game the best strategy, I don't think there much to help on this right now... except the thread (but not everyone knows about it).