Grinder, sorry to disappoint. I can confirm that we intend to do all Magacorporations in time, although only 2 of them will be in the first wave (Cybertronic being one, the other is yet to be announced (it could be any of the other four))
OK, Algeroth, Brotherhood and Cybertronic are very good choices. Not that I played them in the past much. Imperial was always my first choice.
But the three hate each other like hell.
The next MegaCorp will be more difficult but if they want the Mega Corp with the most possibilities it will be Mishima, because Mishima can fight against all three (from the background).
All other possibilities (Imperial, Bauhaus, and Capitol) will normally not fight the Brotherhood. Of course you can find always exceptions but it is most time not true to the story.
It would still a little bit odd to have the both big MegaCorps (Bauhaus and Capitol) not to be part of the first release but still I would recommend Mishima to keep everybody in hate to each other.
Anyway don’t forget to offer team fighting rules. We play most games as 2-vs.-2-team-games.