Spent my last hours in the game playing through "Lair of the Shadow Broker" and "Arrival." Shadow Broker is undeniably brilliant, and my reasoning for playing it after the main game involves my Shepard's relationship with Liara. She and her were lovers in the first game, but in my initial playthrough of ME2 I got with Garrus and wished to preserve that relationship during this playthrough in a plausable way. That meant getting with Garrus before I had the chance to rekindle things with Liara, and that meant doing the mission after passing through the Omega 4 Relay. Arrival is not the same quality as Shadow Broker, but provides an important link to Mass Effect 3, and is thusly vital to my playthrough.