To my understanding, the rare artifacts (planet flux, Terraformer, locker, etc) drop rates were nerfed as the advanced players gained too many of them due to their huge AP/day accumulation, which made the value of the artifacts became very cheap.

As a result of the nerf, it prevented the current beginners from having equal fun that current advanced players enjoyed while they were beginners. In this case, applying different drop rate for artifacts for beginners and advanced players can solve some of the problem.

For example, apply the previous drop rate for players with level below 75 or 30 days of playing (must satisfy both),
and reduced drop rate after that until they reach 150LV or 90th day,
and finally current drop rate after that.

The flaw would be that this system is not CC player friendly, but if they want to advance quicker with CC then they are paying the price for it. It could not hurt them too much, since CC players can probably afford buying those artifacts with $ by saving 4~5 refills.

nice idea, but it would be too easy to exploit. imagine building up farmers for the sole purpose of getting fluxes and terraformers to be sent to the higher level players. it'd effectively throw the balance.

how about slightly increasing the chance of appearance of those npcs that drop these items?

Even with the increased rate for beginners, they'd probably get 3~4 rare items before they go to the intermediate phase because getting artifact production rolling takes time. Growing a ship from 1 to 60~75-ish takes a lot of on-line accessing time & hundreds of signing-in; if somebody was hunting multi-accounts, it would be very easy to spot those farmers.

But I see how it can be exploited if there is not enough manpower to watch for long-term farmers.

Fluxes and Terraformers cannot be traded, so you can't use a multi-account to gather them.

You are right about Terraformers, but planet fluxes can be traded