I liked the pirate/sysdef questline but that mission on the ice planet is really tedious. And Delgado is an annoying imbecile.
But I'm so far on NG+ I don't care about factions anymore. I don't even want to see Constellation again. I go for a "weird universe" every time, only do the "Mantis" sidequest, gather enough cash to buy "Reflection" particle beam and then go planet hopping on my own until I get bored and move on.
"Shattered Space" was decent but has no replay value. It was cool how the enemies were literally the Aldrain from "Land fit for heroes" but no way I'm ever dealing with those Va'ruun morons ever again.