So, I thought I'd try the Cravers and do early war/Conquest...

I crank up a game and get this for a galaxy: http://steamcommunity.com/sharedfiles/filedetails/?id=894887611

Yuck!

I've been seeing a lot of those in the 4-arm galaxy games I've been playing, which surprise me.  I don't necessarily mind them every once in a while, though I have to say my Vodyani game was really weird.  They had one of those long strings way off from the rest of the galaxy with nobody in it. The Sophons spawned in my arm, so we've been fighting for control over that, and the Riftborn seemed to spawn fairly close to the galactic center, and the other two races are nowhere to be found, despite having explored over half of the galaxy, including three of the galactic arms.

A very unusual galaxy shape for 4-arm.

I have made a topic about galaxy generation since last patch because i think it's bugged. I don't think you are specially unlycky. The universe is crawling :C

https://www.games2gether.com/endless-space-2/forum/65-general/thread/24467-help-galaxy-generation-is-bugged-i-am-pretty-sure