I thought the Shivans in FS1 were meanto to be a scouting wing? So I presume they had a limited numer of the really BIG cap ships like the Eva and the Lucifer?
Because the lucifer was invincible it could cruise around with abandon.
And yes we all know WHY you don`t get any help from earth due to the unbalancing issues... That was not the point. This was mroe an issue about the "plot" rather than the game. (although I think having the undefended Lucy against a couple of destoryers would have been cool. I mean the mission dfening the Bastion gainast that second Eva class was hard, you HAD to knock out it`s turrets or it mauled the Bastion at close range.
The undefended lucifer against two sol destroyers one with beams the other without, luci wins, player horror at carnage and renewed attempts to take it out before jumping out. Class.
Oh and Subspace tracking is the most imprtant. They could have used a lighter faster ship or modified transport to jump the needed fighters into subspace. The helios equivilant in FS1 was powerful enough but so could enough typhoon bombs.
So they needed tracking to track the Lucifer and assemble a fleet to stop it. I`m sure they would have done things differently (as in sending in sols fleet) if they didn`t have jump capable fighters
We will however never know.
