So, we all read that there is gonna be some 'clarity' presented in DLC form this summer. This seems to be the compromise, Bioware saying 'Hey, we aren't changing it, but here is your epilogue.' I'm glad about it, as I was absolutely fine with the actualy fact list of what happens in the ending, just confused and feeling abandoned as it all happened so suddenly and then boom, gone. I actually bought into the indoctrination theory, but I guess that's likely not the case now, which again, is fine, as long as it's clear.
So, Bioware has said it's likely to continue the setting, albeit without Shepard. Whith things as they are now, I'd say that I predict two separate games (both potential series) that may come in the next few years.
The first is a setting before the Reaper invasion, perhaps even before the First Contact War, where you are either human and discovering alien life and going through that war, or you are alien going about your alien business and humans aren't even a part of the game. This seems like it would be in proper spinoff territory. This would be the easiest, as the established fiction would be already set. Could be cool, but also potentially a big yawn.
The second, far more interesting to me would take place after the loss of all the mass relays. Now, assuming that the Earth mass relay's destruction didn't blow up the planet (maybe it was more a dismantling or contained explosion instead of what happened to the poor Battarians), Earth is now home to all other known intelligent life, scattered among the ruins. FTL travel is still available without the relays, so nearby colonization is still possible, though much harder. The population of Earth was greatly decreased, and the fleets of the other races certainly can't make up the likely billions lost, so there could actually be room on Earth itself. Isolated in the galaxy, Earth has become the central hub for all races that were part of the battle. With the Quarians ability to live in spaceships, they could share that knowledge with other races unable to breath earths atmosphere (the volus) and potential teach the turians how to create their own food from their ships reserves (ok, that one is a stretch). Earth is effectively the new citadel, though it's probably more Babylon 5-ish, with all the old prejudices coming out stronger from the desperation to their situation.
This necessitates more systematic space exploration, instead of leaping from one system to the next, they all most explore the ignored systems in between. Space Travel becomes a much more time consuming task, but not impossible. While the relays are gone, the mass effect technology on their ships still work, though with limited element zero quantities and so many disparate faction demanding those resources, the alliance is hard pressed to supply all with what they need. The resentment of the other races stuck on earth with few resources and no sense of home quickly other forms of government apart from the alliance, or even terrorist organizations. There are those that get along just fine, but bear in mind, almost everyone there was military and this likely jingoistic in their responses to withheld materials. New allainces and factions emerge over time. Some from political and cultural bias, others from the mere fact they the share the same food needs.
Blah, could be totally different, in reality. tell me you speculations for the future games supposedly planed if they were set AFTER the destruction of the Mass Relays. Could set in some terminus system colony trying to return home Battlestar Galactica style for all we know. Speculate wildly, I'd love to see crazy ideas. Expand on my idea as well if you like. I'd prefer this to be a creative thread instead of just single line replies before being lost in the forums.