You don't think that the Citadel party in Shepards absurdly flash new aparment is oddly placed in the middle of the story about the biggest war the galaxy has ever known? Maybe you're right. When should we play it? Right after the scene where Joker comments on how oblivious the citizens of the Citadel are to the horrors of war, or just after seeing all the refugees cramped into the docking area because they have nowhere to live?
This is why there are references to the war. No one has forgotten it's on. I believe a few people in the military here have pointed out the absolute *need* for R&R. Have you seen some documentries on people who go absolute bat**** after too much combat?
It's ridiculous. I looked the other way on it because I found the party funny and enjoyable, but that's from the perspective of having finished the game and this story acting as a farewell. Taking place at any point before you've defeated the Reapers, this DLC is utterly ludicrous. There's people dying everywhere, and hundreds if not thousands left homeless on the Citadel. Time for Shepard to put his feet up and watch the game with James and Cortez. Tonally, it doesn't fit the characters, and it's completely at odds with the story.
When you head to the Citadel for business the characters are there anyway. There is nothing ludicrous about having some time to recover before going out into the fray again. It's been mentioned numerous times about how necessary that is. The whole "omg it's a big war" doesn't cut it. Yes, it's absolutely vital for Shepard to win this, but not much can be done when your war is against a tireless enemy, who needs no sleep, food or resources to keep on fighting. As long as the Crucible is still under construction, there is not much that can be done. Unless you want Shepard to go around leading evacuations. There is only so much the man can do.
There's nothing inherently wrong with humour in a story, either, even quite a dark story like ME3. But the issue with Citadel is that it's all humour. You play through the main game and you get the odd amusing line in an otherwise depressing tale, and then suddenly after the failed Citadel coup, you get nothing but amusing lines for a couple of hours while the plight of the galaxy is forgotten about. It doesn't fit with the rest of the game in any fashion whatsoever.
If it's all done through one go, then sure. But the DLC is not meant to be taken *that* seriously. Even then, there are more touching moments than there are comedic. The humour belongs to the dialogue, not the tone, and that's where it's always belonged. It's still very 'Mass Effect' when Garrus goes "wait, you're all getting paid for this?"
I'm not trying to bash Citadel for the sake of it, as I'm glad I played it, and I actually enjoyed it quite a bit (the party segment at least) but it's absolutely not without flaws. If you play Citadel during your first playthrough of Mass Effect 3, it would be like watching Schindler's List for the first time and finding out your idiot housemate had accidentally taped over five minutes in the middle with How I Met Your Mother.
Again, you're taking it too serious. As I said, the whole point is a symbolic goodbye to Shepard and company. For a 'last ever DLC' it's fitting to give the fans what they love most.
If you're looking for flow, then the DLC should be played bit by bit. It's all unlocked as you go through the main campaign. My next playthrough will consist of doing this DLC into three parts.