In his review of its Utopia DLC, T.J. Hafer describes the Stellaris base game's undoing as "[not] space itself, but its relatively challenge-light mid-game." I couldn't agree more, and its subsequent expansions, not least Utopia, have served to bolster that intermediate lull.
Furthering this quest for improvement, and in celebration of its first birthday, Paradox has unveiled the Stellaris Digital Anniversary Edition—which includes Stellaris, its Uptopia DLC, Plantoids Species Pack and Leviathans Story Pack. For a limited time, that's going for £39.90/$49.91 over on Steam.
"It’s hard to believe that Stellaris is already a year old. Paradox Development Studio’s science fiction empire builder arrived in 2016 to widespread critical acclaim and found an eager audience ready to transcend the bonds of their home planet and forge a bright (or dystopian) future," so says Paradox. "To celebrate this anniversary, and as a gesture of thanks to the inhabitants of Earth, Paradox is offering a Stellaris bundle with its three expansions."
During this time of festivity existing players are being rewarded too, with Paradox giving away the game's Creatures of the Void DLC pack as well as a new Anniversary Species Portratin Pack free of charge.
For more Stellaris reading and viewing, I'd recommend checking out T.J.'s above linked Utopia review, Phil's thoughts on the base game, why Tom loves its slick interface, and this feature breakdown of the latest expansion: