You nailed it about the gameplay in your guess. It was very cutting edge when it came out. The animations on the plasmids were especially memorable I recall. It’s interesting to hear that part doesn’t hold up so well.
I’d highly recommend you play 2 as well. It’s quite different but I thought it was the best of the series gameplay-wise.
If you like the setting I would also recommend you go on to play BioShock infinite and specifically the DLC for it. I won’t say why, and I recommend you go through the base game first (very cool in its own right), but the DLC is really going to tickle your fancy I think.
I think it’s just purely generated content. If you touch it up a human was involved and it’s fair game afaik