ajburges wrote...
Remember Sovereign states in ME1 that the Citadel and Mass Relays were to guide our growth until they invade at a critical juncture. Our iteration is past that juncture by at least several decades and we've had 2 years by ME2 to reverse engineer Sovereign tech and a further .5-2 years to study it and the Collector tech. It is plausible at this point that a new technology they haven't/can't prepare for will be available by/during ME3 to defeat them. This tech has already shown large dividends compare Normandy, SR2, and SR2+ (fully upgraded) vs the Collector ship.
Additionally Reapers have been playing the arrogance card heavily all series. If this is true arrogance, then they may not assess when to retreat properly.
Finally there are several hinted areas of additional galactic force multipliers:
True Geth
Quarians
Genophage cure
Rachni
Shadow Broker Network
Bioware pulling a McGuffin from...
And possible wildcards of greater than expected importance:
Ferros (via Thorian influence)
Promethean artifact
Remnants of project Overlord
And Jessie

. Blood thirsty old b*tch!
The more I think about ME1's story, the more I am starting to wonder whether we (myself especially included) are under estimating what Shepard has done to thwart the Reapers. For millions of years, the Reapers have managed to cycle through all intelligent life in the galaxy, likely unhindered by most races. A few were probably tough, but most, having no knowledge of the threat beyond the outer rim, could be wiped out fairly simply. And then, against all odds, Shepard and Vigil threaten to cause mass delay after mass delay.
Think about this:
Most of the time, the Reapers entered the galaxy via the citadel. Until Shepard's time, the secret of the citadel had never been stopped by any race. Ever. The citadel is instrumental in understanding all organic species, their governments, their locations, their forces, their hideouts, and, most importantly, the activation of the Mass Relays throughout the galaxy. With the citadel's control wrestled away from the Reapers, they will have to take the hard way, slowly squeezing every civilization from every corner of the galaxy. With the citadel's ability to close off Relays, so long as the citadel is able to remain in the control of the council, they can completely hinder the Reapers movements. The Reapers
would only effectively attack one planet at a time, and would have to say together to do it. Splitting their forces up, and jumping to several different systems would be completely futile when the council races could shut down their own relays. The Reapers would have to split themselves into groups of hundreds, and jump at FTL for months to systems that would be well fortified.
But Shepard's damage to the Reapers goes deeper than that.
The collectors, like the keepers, are either dead or scattered and useless now. The Reapers infield spies and agents are gone.
Now the Reapers have to rely on small science teams within the galaxy to stumble upon Reaper "antennas" like Rho, and the husk building machines to get any information they want. We've seen it time and time again. Rho. The Prothean Relic. The Reaper husk hub. Etc, etc. These are probably more like small land mines than actually anything important, but if a small science team can inform the Reapers about the daily lives of a star system, it may be enough to formulate a plan.
Now, no matter what, the Reapers obviously have back up plans. They tried to jump directly into the system, and use a Relay to launch their assault on the galaxy. When Shepard destroyed that system, Harbinger was annoyed enough to tell Shepard off. Could it be that, with their initial infiltration of the galaxy being so utterly crippled (particularly with the loss of the citadel) that the Reapers will make an error they never initially anticipated: hastiness? Is it at all unreasonable to assume that the Reapers assault on the remote planet of Earth is to demoralize the rest of the galaxy, when in reality, it could be the very banner Shepard needs to wave to inspire all of the races?