The problem if this. The modles are legal for poliy limt but WON'T convert from .cob to .pof
That core fighter is comming along nicely!
It can be the standard fighter for support ops.
Also if the pilot of a Gundam has time to eject before the mech explodes this is what will warp in as the Gundam is built around the core fighter (which controls the Gundam).. Not every mech needs to be killed "twice" but the more experienced pilots will be harder to get rid of permanantly (which is why they run away and you see them in later episodes fighting again)

When forced to eject in the core fighter most pilots high tail it back to their base. Only the most skilled or suicidal stay and continue fighting.
Seriously the core fighter , while a threat, is not gonna be used extensively. You won't see whole fighter wings of them, but occasionally 1 or 2 along with mechs.