I like the fan edits best, too.
My personal version embroils Shepard and her squad in a suicidal guerilla attack upon Harbinger, drawing the Reaper's attention in a series of covert strikes that are requited with deadly force. As Shepard and her friends dodge from ruin to ruin, escaping the death ray by a hair's breadth several times, Harbinger unleashes the most devious weapon as well, attacking their minds with indoctrination.
Shepard continues to defy Harbinger in spite of her weakening resistance, but at some point, the squad mates can no longer withstand the onslaught:
Liara pins Shepard against the wall, her eyes empty black holes, muttering: "It's over, Shepard" just as Harbinger's voice repeats the words.
Shepard ceases to struggle, and sags with what seems to be despair - and then she starts to laugh. Softly at first, so softly that it might just as well be a sob - but it soon becomes apparent that what we hear is not the sound of defeat, but of something else entirely.
And then, we notice the communicator in Shepard's ear, broadcasting: "... repeat, this is Kasumi Goto. We have infiltrated the Citadel. The diversion was successful. The Crucible is docked, armed, and ready to fire in three, two, one..."
Harbinger emits a bestial scream that is echoed by the thousand throats of its thralls as the pulse hits the earth, disabling the Reaper's shields and momemtarily stunning it. The Normandy charges over the rooftops, bringing its thanix cannons to bear on the lord of the Reapers, just as the rest of the united galaxy seizes the moment and strikes back at the Reapers. The Rachni and Krogans mow down the ground forces alongside the Elcor tanks, Aria's mercenaries fight dirty in the orbit, and the geth reverse-engineer the mind control pulse to incapacitate the Reapers even further. All across the galaxy, hope is rekindled as the pulse is broadcast across the relay network, giving the species of the galaxy something that evens the scales.