Yep. Nazi's are good foes-very effective.
But how about some Ouroboros content that features fighting on the Rikti Home planet? Let's take the fight to them!
Either Vanguard has a very closely guarded secret Rikti portal that they have been trying to harness and finally use...
-Or-
The Menders take a chance to go to the time when the Heroes were sent to the Rikti home world on the suicide mission to eliminate the portal and stop that from happening...
-Or-
Earth finally has had enough of the Rikti and decides to start invading their planet by means of one of the above mentioned...
-Or-
...the options are endless. The content could be offered as a special badge mission (with accolade powers AND special costume pieces or other big time rewards) either after completing the Ouroboros TF's or after completing all of the story lines or both.
Just my two cents

. I've been playing about 4 1/2 months now and I love all the content on both sides. Unbelievable game-keep up the great work, devs!