Some ideas I've had. Tell me what you think, and don't hesitate of you have ideas or whatever.
Factions
Talon Corporation
Formed by the merger of three Private Military Companies operating out of South Africa, Argentina, and Austria, the Talon Corp is one of the most vicious and uncompromising PMCs in the world today. Operating all over the globe, they bring brute force and terrifying brutality to any strategic or tactical problem.
But there is a darker secret hidden in the Talon. It's leader, 60 year old Edvard Pieterzoon, is a South African Boer who espouses the ideas of National Socialism. Not only that but his father was Otto Ganz's aide de camp, serving in the SS during their worst atrocities. Pieterzoon has been searching for Nazi artefacts for forty years, and the clue recently discovered in the Berlin war archives could lead him to the greatest Nazi artefact of all-greater than even Pieterzoon could have imagined.
Talon Corporation is led by Edvard Pieterzoon and his second in command, Patrick Collins. It is based in Pretoria, South Africa.
Special Operations Executive (SOE)
Named after Winston Churchill's wartime sabotage agency, the SOE is a clandestine organization whose aim is to combat fascism and totalitarianism in all it's forms. Its operatives have fought in Spain, South America, the Balkans, and in Iraq and Afghanistan (religious extremism is viewed as a form of fascism by the group). The Talon Corporation is one of the SOE's most powerful foes, and the SOE is just as interested in getting their hands on Ganz's facility as Talon Corp. They have also heard about the discovery in Berlin, and are making moves to obtain it before the Neo-Nazi mercenaries do.
Relying on highly motivated volunteers and the financial backing of several powerful individuals, the SOE operates in small cells that can handle both espionage and combat.
The Special Operations Executive is led by the mysterious Council of Five. Its' HQ is hidden deep underneath London, in a WWII era Underground station.
These are the two main factions. Others- like governments, police forces, militias-will come later, as they appear.