The Ackbar Gunnery Team combo took me off surprised as an inexperienced Imperial right after Massing at Sullust. I did play with 2 Victory and 1 Gladiator, along with a few squadrons. I played my list as a gunline which worked okay with Wave 1 meta, but was bad against that specific combo (I even had Opening Salvo on my objectives, which the Ackbar player gladly took). By Turn 3 the game was done and I think I only destroyed 1 Corvette overall.
A few key points to note from that game :
1) The Gladiator flanking his front and rear arcs was pretty amazing. Ackbar loses so much efficiency.
2) Because of that, positioning on an interception course is almost mandatory.
3) Squadrons allow to delay positioning
4) Imperials are now outclasses as a gunline and I think this pushes them back to a brawling playstyle exclusively
5) Victories, being prime carriers poitns for points, could help out the Imperial by offering 3 deployment if they coordinate 4 squadrons.
6) Pairs of Rogues allow for cheap placement of ships, delaying where you key pieces will need to be.
7) I don't think speed 2 was such a liability for the Victory. I did manage to reach black range on the Ackbar fleet without much trouble. It was dropping one Victory to speed 1 early game that sealed the deal.
8) Assault Frigates are scariers than Calamaris due to Gunnery Team, but they still die out relatively easily.
9) Captain Needa giving an Evade on a big ship should help a lot with tanky ISD 2 builds.