Personal opinion here obviously: Mass effect, or at least the first one, was actually surprisingly well written and internally consistent. Kind of like a star trek lite. There was interspecies tension, people expressing feelings on the state of the universe, but also enough moustache twirling to keep it interesting as well. It struck a good balance between that and a decent looter shooter/RPG combo, at least for my tastes.

The later games lost a lot of that and overly relied on what the first game setup up without expanding much on it, but that first game was just chefs kiss.

Not saying you're wrong or anything, more just this is what I personally get out of it.