Well, my latest seed made on latest beta, I have NO alien circle of Asteroids to put my Artifacts in. Doesn't exist. And I went around the entire core rift wall checking.
No mad scientists at all either and multiple hidden mass sectors with nothing and I mean Tab only brings up me nothing. What feels like about half the ones I checked
Also About 10 different fractions have warp gates bypassing the rift.
I might play again after a new patch comes out.