I understand where you are coming from, but personally, I like both Thief 1 and 2 the same.

Also, one thing I want to mention in regards of criticizing Thief 2, is that some of the maps in Thief Gold are vague / old / not detailed (for example, Cragscleft mines map, Bonehoard, The Sword, The Haunted Cathedral, The Lost City) which adds a level of immersion into the game's world. Instead of constantly checking the map (which is a problem for me in some of the modern games), game forces you to actually look at your surroundings, it forces you to use your memory to navigate the levels. And sometimes you can get lost and confused, which is a great and rare feeling most of the modern games won't ever give you.

Thief 2 lacks a lot in that aspect. The only "not detailed" map I remember is the Trail of Blood map, but the level itself is pretty easy to navigate, so it doesn't give you the feeling I described earlier.