Mass Effect 1 spent a huge portion of its attention on world building. And I agree, it's an outstanding achievement. Mass Effect's world is a very compelling pl

Mass Effect 1 spent a huge portion of its attention on world building. And I agree, it's an outstanding achievement. Mass Effect's world is a very compelling place. But by the time you get to Mass Effect 2, that world is already built. So ME2 instead spends its time telling a more contained story in that world. It's a valid choice, even if not your cup of tea. ME2's story works because it's a relatively well executed Seven Samurai-style plot. We've seen this story many times before. It's a classic. Sci-fi stuff threatens the galaxy, assemble the crew, watch them love/hate each other through tough challenges, some don't make it through the epic conclusion, etc. Standard. For a lot of people, it's fun to relive those story beats in an interesting new world (Mass Effect) in a novel format (video games). I think of ME2 as a smart and enduring example of video game writing craft. They were juggling a lot of different requirements: player choices affecting the story (including from the first game); a huge, complicated new setting; making the story accessible to new players without needing to play the first game; developing interesting characters; supporting multiple protagonists (male/female, paragon/renegade) and varied character interactions based on those attributes; supporting high production values (all lines voiced by real actors); fast development timeline; on and on. Hanging all of that on a familiar plot structure probably brought a lot of structure to what was otherwise a pretty chaotic project. Furthermore, what ME2 does better than other games in the series is let characters drive the action, rather than dragging characters from event to event. The writers did an amazing job on ME2 in context.