I'm with you here, but I think part of the problem is that if they did play the nostalgia card and you got on the Autumn, it'd be hard to get off the Autumn in a way that didn't seem like an ass-pull. Think about it: you're on the Autumn fighting off waves of brutes, skirmishers, and anything else the Covenant's trying to throw at you in their last stand, and you're expecting to take off with the ship. Then, suddenly...
"Cruiser! Lieutenant, there's a Mass Driver rigged up seven clicks from the starboard bow. I need you to take one of the Warthogs from the vehicle bay and take it out. Given how far it still is, I'd say you've got six minutes..."
dammit, wait, I meant that to sound bad :lol