I only played the original. I didn’t really like it at first, thinking that the augmentation and mod stuff was needlessly complicated for this kind of game. Also the graphics weren’t all that great in comparison to other games using the same engine. There were a lot of attention to details in comparison to other games so I gave it a chance. The turning point came after completing the first part of the story and getting hooked. The story really carried the game and touches on some interesting topics.
A game with a similar feel would be Omikron: The Nomad Soul. It was released the year before Deus Ex, has worse controls and graphics, but the story and setting is somewhat similar.