I disagree with this. Imo I think Mass Effect 2 had the best version/interpretation of the Citadel. Whilst i agree ME1's was bigger, i felt in going for that scope it sacrificed depth & detail in the process. It was as wide as an ocean but as deep as a puddle.
I think you're disagreeing with something I didn't actually say. I simply said that it felt big and contiguous in ME1. I liked the feeling of open walkways and what not - the closest we've seen since is ME3's Presidium Commons.
I also suspect you may have forgotten some of the side content in ME1's Citadel. Preaching Hanar, Couple arguing, Helena Blake, Consort Sha'ira, shops, Chora's Den, Flux, Dr. Michel's clinic, Emily Wong quests, Conrad Verner, Keeper Scanning, AI tracing, Convincing Ranna not to work undercover for C-SEC, etc. - there was actually quite a bit going on there.
The only Citadel sidequests I remember from ME2 were the Krogan wanting fish from the Presidium, the Quarian accused of theft, and some Asari complaining about new transportation rules. You could also talk the shopkeepers into discounts.
Both ME1 & ME2 offered sidequests on other hub worlds (Feros, Noveria, Omega, Illium).
With a reaper invasion in ME3, the additional hustle and bustle makes sense - though there have been times when the Citadel activity in ME3 sort of overstimulates me. The constant news announcements plus ambient conversations plus anytime I access a shopping kiosk, it starts talking... there are times when I mute the sound in that area so I can think.
I loved the rich atmosphere also(ME1 hooked me in, but it was ME2 that truly engrossed me, made me fall in love with the universe).
ME1 did it for me.
I really hope Bioware are able to recapture that vibe. Though i feel like for sme reason that won't be the case. Games like that don't come around to often. But i do agree with you on the airlocks/docking/lifts etc. That should've never of gotten axed. I hope they bring that back for ME:N. The immersion factor from that you can't beat).
I suppose the honeymoon is over - lol - but I expect Bioware might have some exciting new things to discover in ME:Next. I guess we'll see.