Even if it is a Shinji Mikami Greatest Hits collection, the enemies are just that much more unique and terrifying.
TEW1 is a more interesting world and story. This is especially true if you compare how both games were on launch TEW1 was an absolute technical disaster for the first few months. It has issues, what with Stealth being the easy solution to almost every problem, but on average it just feels better to play around in. TEW2 handles much better with a more responsive UI/UX and a larger selection of toys to play with. It wasn't nearly as charming or interesting of an experience.