Yeah I'm a big fan of Invisible War too and can recommend it. It's a bit too Jetsons (its depiction of the future is cartoony compared to the first game), but yeah it's still great stuff. I first played it a few times over on the Xbox back in the day before I had good PC's. I'm sure that version is still fine. I played the PC version a few years ago finally. The hilarious thing about the PC version, is that the game literally crashes itself in between loading maps... something to do with how it flushes and resets the memory usage of the game or something. It was a bit of a mess to get running on Win7.
I actually found Thief II to be just as tense as the first game. There's just something about those slurred, monotone robotic voices - 'I have... heard... a malfunction...'. Not to mention the people who got turned into Children of Karras or the spider robots from the last level. Speaking of which, I remember there being some sort of chapel in the final level. As soon as I picklocked the door, I was greeted by a long dark hallway. At the end of it, there was a little robot child staring at me for awhile before it started running in my direction. I immediately closed the door and thought to myself ' Yeah, well, this level is hell as it is without having to deal with something out of the Shining. I guess I'll find another way.'