That's fine, eventually, while playing more and more you will acquire every possible artifact.
I am now on Europe 1066 AD map and have all artifacts that are in active use uncommons and rares. What's fun, I got only 1 rare from dig, all others are from upgrading. (army camp boost from poor to rare and bonus money boost from common) I sacrificed some good uncommons such as sell price for ores and items, more ore from mines, efficient crafters and smelters (on uncommon they gave only 2% discount)
What is really depressing, when you get to larger map you don't get any increase in number of digs with good chances for uncommons or better stuff. On some map that required like 1 week to win I got lots common (big chance) / uncommon (low chance) digs, now, playing 2-3 weeks maps I get lots of 100% commons and sometimes 70% poor, 20% common, 7% uncommon, 3% rare or something like this and on very rare occasions 99% poor 1% epic (never got epic from this one). It is usually everything for poor/common... like junk, because you are wasting them to upgrade to uncommon to be able to waste to upgrade to rare something useful.
But that's fine, uncommon bonuses are already good enough for unstressful play :)http://prntscr.com/xjglxi
Edited 1/24/2021 09:05:31