It was? Seems to me you just added the destroyers.
Before they arrived in system there were 3 GTVA destroyers 4 before the Carthage was lost
these ships make it 5 - as I said I got these figures from the forces deployed in sol thread.
You're missing the smaller ships attendant to the GTVA destroyers, however -- cruisers, corvettes, supply craft, not to mention fresh fresh pilots and munitions. For example, if the new battlegroup has any Anemoi logistics ships with it, the way Bei's 14th Battlegroup did, the UEF is in serious trouble. Nabbing that Anemoi in R1 was such a coup in part because of how few of those ships were in Sol. If Steele can bring in more, that gives him more leeway for large resource-intensive ops, while the UEF has no real way to respond. Each side's fleets can only afford to take so much damage before the fleet would become useless, but the new battlegroup increases the damage the GTVA can deal with; they can repair and restock via the Anemoi, and swap in fresh craft and men from the battlegroup itself.
Much as I prefer the UEF, things look even worse now than they did at the end of R1!