I recently replayed the trilogy and tried out Andromeda for the first time. I don't want to talk about the ending of 3 because it's been discussed to death, but more about the direction of the series and some of the underlying themes.
In Mass Effect 1, the central idea is about humanity's place in the galaxy: will they work together with the council species or advance their own interests at the expense of everyone else? The framing itself is (although not that unusual for fantasy/scifi) worth commenting on because every species is governed by an ethnostate, and representation on the council is through a representative from each ethnostate deemed worthy of joining its ranks. The games never reject the framing either, only examining some of its consequences like the sterilization of the krogan. Humanity's government is expansionist, militaristic, and dominated by corporate interests, with entire planets handed to corporations for colonial settlement.
Other species have corporate worlds as well, the asari in Mass Effect 2 are even shown to have a world with legalized slavery. Mass Effect 2 drops Mass Effect 1's theme and goes for a "grittier", action movie/heist story. Andromeda tries to address them but they lose all salience when the conflicts are an entire galaxy away and 600 years in the past. 1, 2, 3, and Andromeda all bring up AI and organic/synthetic conflict but they take it in 20 different directions and use it as a convenient plot device more than something to explore.
The art and music for each game is great, and the combat and level design gets progressively better with the series, but it really feels like they lost the sense of exploration the first game had. Not as in exploring with the Mako, which sucked, but reading planet descriptions for interesting tidbits and getting the sense that the galaxy is much bigger and more mysterious than the player will ever realize. With each installment the galaxy feels progressively smaller as the overall stories get more focused, but the pacing isn't any better for it. Looking back, the Reaper invasion seems like the wrong direction for the series, and I sincerely hope they aren't setting up for another synthetic vs organic storyline but that seems like all they can write about anymore. I expect they'll lean even more into action movie explosions-and-narrow-escapes stuff with 4 as well.
Hot take: half the squadmates in ME2 didn't ePost too long. Click here to view the full text.