I didn't HATE it, but it did seem abrupt. I am fine with the overall setup of the ending, the child, Shepard's choice and all that. I'm fine with Shepard sacrificing himself and not reuniting with his friends, not every ending has to be happy, and it fits.
I chose the "All synthetics die" option because the kid only mentioned the mass relays being destroyed in the "Control the reapers" ending, but I guess the mass relays all get destroyed anyway? So now galactic society is basically totally

ed? That sucks.
I just didn't really get the whole part with the Normandy landing on the alien planet. For one thing, Liara was with me at the Conduit, and supposedly everybody there died except Shepard and Anderson, yet there she is alive again and somehow back on the Normandy? I guess I'm glad she survives, but it doesn't make any sense. Garrus was there too, and he was down in London. Did Joker just pop down to the surface while Shepard was on the Citadel, scoop up some people, and then head to a mass relay? Why would he have done any of that? And what is the point of them taking a mass relay and crashing on an unknown planet?
I just didn't really get the point of that scene at all and I would have preferred an ending where the two people on your squad died at the Conduit, and everyone else is still in London, starting to rebuild.