I think the one fatal flaw that people make when analyzing Mass Effect 3 is not realizing that the entire game is an ending. Each mission arc is resolving plot threads from throughout the series. By the time you reach Earth at the end, there's only a few things to take care of. If you just look at the last five minutes of the game, it might feel anti-climatic, but when you take the entirety of it as a conclusion, it's quite fitting. I thought my Shepard felt immensely personal by the end of it. I didn't need to see every single person that I had ever helped come to the final battle in order to feel like my choices matter. The finale isn't perfect (I wish there was more of a legit confrontation with Harbinger, though I realize he just gets ghosted along with the rest of the Reapers), but with the Extended Cut in there and the extra context from Leviathan, I actually really enjoy the Earth stuff now. It's a solid, emotional finale to the trilogy.
Got tired of the filler crap and side stuff (even in the vault territory of things) in between actual missions and character development, but quite enjoyed the story and characters. Probably liked it more than ME1 overall, which I also love, so it's a good starting place for the future. Curious to see how future DLCs develop it.
Still playing and enjoying the game. Things that I mentioned that annoyed me still do. I'm feeling the pressure of other games now and I may start limiting some missions that I do. Some of the side quests just seem like busy work which is fine cause it's fun to actually play the game but there ant much story merit to those missions. I may just start hitting the primary missions and secondary/loyalty missions. Those all seem to have the most depth. For anyone whose beaten the game, would I be missing anything special if did this? The problem is I got a switch somehow this weekend so of course I got Zelda and Persona 5 comes out next week. I can juggle 2 massive rpg games but 3? I'm not so sure....
I'll say this much: find the arks, and find all of the memories. The first is really the primary thing that affects the ending (and it's only one detail), and the second just has a cool payoff. The loyalty missions are all cool too. Honestly, most of the other stuff and random side missions on the outpost worlds, accept for maybe the vaults (but even those are questionable), really have tiny, primarily gameplay focused effects on the ending, if they have any. Honestly, most of the choices in the side stuff seem like setup for future DLC/sequels.
@alex: Obviously, if you don't want to do it, then by all means, don't do it. That being said, I don't think something like this has to be implicitly negative to be entertaining. Sure, there will be moments of garbage to laugh at, but often times some bad games can have some really fascinating ideas behind them. Martian Gothic is a good example. Utterly awful, but there are some interesting things in there to discover and experience. Same with stuff done on here prior, such as Bioforge. Again, I'm not putting any pressure on anything, I'm just saying I think this could be something that both enjoys the failures and unexpected successes of "bad" games.
Another one for me is Syphon Filter: The Omega Strain. Don't get me wrong, I love that entire series, but that game...man, I dumped SO MANY HOURS into that game, trying to unlock every little thing. I very rarely become obsessed with games like that, but I adored that game. Something about it just really clicked with me.
And a bonus one: Dante's Inferno. Really wish that got a sequel, because that would've been fascinating.