My idea for an awesome (in my personal opinion) storyline for the next game:
First map:
Cutscene shows shadowy figure banishing Richtofen (this is in the Die Rise comic form) and then Maxis laughs.
Richtofen (blue aura) is falling toward a red pit, then freezes. A distorted, demonic voice is heard: "Maxis cannot be allowed to destroy the world. This is your chance for redemption!" and his aura is frozen into the solid shape of a blue man. (Rest of cutscene will be added in a map idea I'm writing)
Then, throughout the story Richtofen works on gaining control, not via the towers, but via a 3rd way to enter the MPD with 3 new combinable artefacts to create a new Vril Generator, the Domination Device, and all the while slowing Maxis' roll of destruction. The Earth is beginning to tear itself apart. (But remember, Maxis didn't gain full control. He simply had enough power to remove Richtofen. He still needs to finish the job.)
Through this story, it is revealed that there is another Pyramid in Hollow Earth which can be taken control of, an override switch if you will, and this is what Richtofen aims to do if you follow his side of the story, and if you follow Maxis' side you aim to give him control of that too by building the Domination Device but charging it for Maxis by using electricity, compared to charging it for Richtofen by killing zombies in a certain area.
NOTE: In the O4 maps the 4th player is RichtoSam, not Richtofen. He serves more of an NPC role in this, communicating as a voice.
Once this is all done, all the Map EE's completed for the same side and the HEP (Hollow Earth Pyramid) reached, an Origins-style ending can be triggered by "Hold [use] to insert Domination Device" (There will be no trigger if the host hasn't completed all the EE's for a side)
NOTE: This ending is the same for both paths, however the Sided EE's do not come without a reward. A nice hefty 100G cheevo: "Loyalty Is No Match For Power" for Richtofen, and "A Father's Love is Limitless" for Maxis' and a special Gamerpic of a skull with special designs tailored toward whichever side you completed. This also resets progress and allows for the opposing side to be completed.
This cutscene shows Takeo holding the Device, which is glowing depending on which side you just completed, and walking toward the Pyramid while Maxis and Richtofen trade insults. Whichever side you did's being will be saying how he is so proud of your efforts and the opposing will be saying a bunch of stuff about how "it's not too late to change" and Takeo walks toward the Pyramid, surrounded by the rest of the O4, it opens, and Samantha rises from within (The Sam from Origins), saying "Surprise! So nice of you to bring me the Device, Edward!" and Richtofen curses, saying that the voice telling him what to do to assemble the device must have been Samantha, and as the Device floats into the HEP and Sam's eyes begin to glow yellow, it cuts to black.
Well.
I want to do a lot more expanding on this.
Treyarch pls use.