I noticed the Take It Back! quest was open and so I went to the Citadel. However, 10 mins in I remembered I'd already done it 5 years ago - the Purified Water one - & finished the game but here it was again. I just couldn't be bothered. However, I've just read that to play the Broken Steel DLC I have to finish that quest (again) to continue on, because without BS you cannot wander the world after the game completes. Hopefully I'll find a cheat that works. So far none online work.
My thoughts on the game years later is it's not as full on as I thought. My character is far less immersive than say in Skyrim. When I change the camera angle to swing around and see characters I'm talking to on quests, I turn around as well which is weird. Far more stiff. It's fun though revisiting lots of places I've forgotten about and I'll do the runaround before venturing on to the DLCs.