It's interesting how the original Bioshock is able to just ride almost solely on it's atmosphere and story to video game classic status. Even in this thread, the main points people are bringing up against 2 is that it doesn't have any good twists or the atmosphere is recycled.
I mean, I'm not mad at that or anything. If anything, it's a testament to how well done to journey to and through Rapture was done in the original, but it does always make me re-affirm my stance that the actual act of playing through the first game is serviceable at best, clunky and repetitive at worst. I finally played through the whole thing with the Collection, after years of repeatedly starting it and telling myself to force my way through the whole thing.
I knew all the twists and story outcomes for a long while, so the magic of wanting to see what happens wasn't there for me, so the only thing really intriguing for me was the atmosphere, but, well, you've seen the vast majority of that aspect within the first hour. I'm glad I can finally say I finished it now, but hell if I'm ever going to replay it.
On the flipside, just 30 minutes into Bioshock 2 felt much more smooth and less frustrating, so I'm eager to see it through to the end.
(I think Infinite is also more fun to play than the original, mind you.)