I've seen a lot of people complaining about the change of setting, saying that they're throwing away the Milky Way. I've seen some people say that they should "face up" to the divisive endings by addressing them in the next game. And I've seen some (silly) people say that changing the setting nullifies the original trilogy and makes it entirely pointless.
What I don't see are ways that they could have made a sequel in the Milky Way that doesn't require canonizing an ending or homogenizing them all together to erase any ramifications of the separate choices.
Any ideas?
The best answer I could give isn't economically feasible. But if you want the best idea I've come up with here you go. Before people start to crap all over it, it was conceived and punched up in like 10 minutes. So here goes:
Three separate game modes I think with incredibly creative writing and a fair bit of sleight of hand, you could share the vast amount of resources through shared locations. The biggest resource waste would be all the different text you would need. I still think the vast majority of the game could be the same with a big of creativity.
The three endings could even be coded towards difficulty levels. Synthesis is easy, Control is normal, Destory is hard.
Storyline: A highly intelligent race (Elder Race from now on) has managed to elude the attention of the reapers, and all others, for a few cycles because they managed to harness the power of Dark Energy through a Convenient MacGuffin®. But their ability to use Dark Energy (DE from now on) is limited in scope. At best, for the last 100,000 years they've been able to hide, but they've worked to weaponize their knowledge and end the reapers once and for all. The Haestrom issue was a weapon experiment of theirs in the final stages.
Synthesis: The Elder Race has shielded themselves from the effects of synthesis using their DE devices. They view the synthesis of organic and artificial life as abhorrent and will the result in something even worse than the reapers in the future. They are rushing to weaponize their DE to purge the galaxy of all life and rebuild.
Synthesis Gameplay: Easiest because of incorporation of technology to organic life. Rudimentary auto aim enabled. Auto regeneration of health. Some unique side quests.
Control: The Elder Race has shileded themselves, but now see the reapers as governed and fear that they will soon be found. They are rushing to weaponize their DE to purge the galaxy of the reaper threat once and for all. They view the intelligent species of the galaxy as all indoctrinated, and thus no better than the reapers.
Control Gameplay: Medium because more infrastructure means more bases, more shops, easier exploration. Some quests are solved by utilization of the reapers. Some unique side quests.
Destroy: The Elder Race sees nothing but seething chaos in the remains. They want to rebuild but view the intelligent species of the galaxy as unintelligent monsters. They wish to weaponize the DE so they can put the intelligent species of the galaxy under their control as slaves and rebuild the galaxy in their own way.
Destory Gameplay: Hardest because the galaxy is in absolute shambles. Very little infrastructure, very little support. Lots of races are in conflict with each other as outright civil war breaks out. A base that's fully functioning and have quests in Control might be filled with hostile mercenaries in Destroy, for example. Less quests, more fighting.
Just some rambling thoughts I threw together while cooking.