"Goose Laying Golden Eggs Slain; Owners In Consultancy With Creators of Turducken Regarding Re-Assembly"
Okay, a little harsh perhaps. But if they've actually learned something from the uproar, my humble suggestion would be:
1. Self-contained game, not the first of a trilogy.
2. More personal and inter-personal plot arc, rather than another "fate of the universe" thread.
3. Resist the impulse to give every surviving character from the earlier games a walk-on.
4. Ditch the military aspect; work with characters who are less beholden to a central authority.
5. Work on creating more situations that involve solutions other than shooting your way out.
6. Don't piss off the fanbase even more by suggesting a problem that was clearly and cleanly resolved in the earlier games, especially one that characters sacrificed their lives to resolve, is returned and/or has dangling threads.
7. Use this as an opportunity to develop or flesh out world lore in ways besides virtual encyclopedia entries.
8. Mineral collection is busy-work, and pretty much always has been. Either find a way to make it more interesting, or drop it all together.
9. Try not to punish players for not playing all-the-way Paragon or all-the-way Renegade. Kind-hearted people sometimes have to make tough decisions, and rough, play-by-their-own rules types still have their moments of tenderness. It's called "role-playing".
10. Some people have no interest in multiplayer. Be okay with this.
'Kay, Bioware? Call me.