I have only played ME2, when it came out. Which puts me in a lonely boat I am sure. Anyways, given the choices at the end of ME2 I had figured ME3 was going to offer a split path. One that worked with the illusive man and one that didn't.
Both paths would involve a final showdown with the reapers, but what kind of a showdown was going to be the difference. The path that works with the illusive man was going to be morally questionable, but tactically viable, utilizing the discovered reaper tech against the reapers themselves. With a revelation at the end that Cerberus ends up constructing it's own reapers out of populations spread around the galaxy with forced soylent camps. When the reapers are defeated the illusive man stands to dominate the galaxy. Shepard either embraces this or is reviled by it. Either way the reapers are defeated, but at what cost.
The other option is to give the illusive man the finger, and form a coalition of all the sentient groups in the galaxy to fight the reapers. This, I assume, would follow more of the current story of ME3 before the ending sequence (I don't know I didn't play it) Here you are not only trying to get the diverse factions to work together, but you are also in contention with the illusive man who is still going ahead with his scheme to build his own reaper force. The personal connections Shepard makes would be vital to swaying the influential members of each race. I thought this path would be the natural self sacrifice path. Shepard makes things more difficult for them personally by not working with the illusive dude, and ends up paying for it.
Anyways that was what I suspected was going to occur given the way the ending to ME2 played out. So when I heard about the really disappointing ending to ME3 and the direction they chose I kinda lost all desire to finish the series. Maybe I will try it someday, but it just doesn't seem worth the effort at this point.
