Large Ships in the All-Out Assault are AWESOME. I'm so bummed Twitch didn't save the video from our AOO yesterday: two built-out ISD1's dropped out of hyperspace right in the vanguard of the Rebel fleet and greeblehauled its core ships on turn 2. It was probably the most Star Wars thing I've seen in this game yet.
I think each player on a team making it to the AOO with a large ship can definitely be a strong advantage here. If you're putting in small/medium ships, you have to put 2 into hyperspace per player , and can only jump them in one at a time (per player). Large ships, on the other hand, only go in one per player, and can all jump out at once. That means, in a 3v3, up to three ISDs, Liberties, or MC80s in a single round... That is just a devastating amount of firepower to drop in a huge area of the board, all at once.
Also interesting to note, though we didn't do it in our campaign, is that each player can opt to move a hyperspace node of their choice, if they choose not to jump in a ship. Which means, again in 3v3, that if you set it up right you can have one or two players move a node to put it in position for the third to drop a ship pretty much anywhere on the board they choose to go*!
*slight exaggeration, but not much