"What if" missions of course.
What if cpt. Cromwell didn't take on two Longswords but retreated after saving Francis' and crew? He has to lay in ambush near the place the OSEC expedition would return to if succesful: Ganymede.
And on the Raptor Genocide mission there are 2 other task forces chasing Raptors in the Scoratus system. According to how much secundary tasks Cromwell achieves during his visit to Earth,
Angelwing is assigned to either Alpha, Beta, or Gamma task force.
There's a secondary task in the first mission of the Gorg section (Episode 3): take out all Gorg ships. If you don't succeed, you need to chase them to one of those Gorg mining posts in the system instead of saving the Ghost scout.
Episode 4 could be lengthened with a few interventions when rebel Gorgs try to interdict Noah transporters.
The Episode 5 Beta gate mission could be extended with a mission in the Equitis system in case the mission is adjusted so that one of the Mech infected Vardrag ships has a good chance to jump through.
And, a whole new campaign direction could be taken if for instance the
Angelwing was destroyed at Shukenja Alpha, at Ganymede or is lost during the Kissaki attack on the Sunflower base.
For instance, Frogger's Borelis wormhole link could be used as the staging ground for a new direction without any link whatsoever to Mechs, Noah, Vardrags. Just 'old'-fashioned Earth ships, the ISA and OSEC/Kissaki trying to kick off something in Borelis. The discovery of a new wormhole around say the Pallas asteroid (Borelis link) would sure as hell compell the ISA and its allies (SpaceTech for instance) to try take a hold.
I think I still have partial missions, or the setup for them, for a Gamma&Beta task force, and a Ganymede retrieval mission half-coded (if the code still works), with changes to Ep1 Mission3 so that it jumps to Ganymede instead of Shukenja Alpha.