I'd heard about Thief for years, but never played it before now. Honestly? I can see why people speak as highly about it as they do, and where a lot of later games would take inspiration. Your visibility is based on both the lighting you stand in as well as whether or not you're crouching. With the right placement, you can stand still in the shadows as a guard passes in front of you and bonk them on the head with your blackjack when they're close enough. It's very satisfying. That said, the levels themselves are relatively simple to navigate with your compass, but I wouldn't rely too heavily on the provided maps. They work, but they're better for getting your bearings than anything. Thief itself has aged, but not poorly. There are a lot of neat ideas that I wish more games would use (water arrows, for example), and I really want to play Thief 2 as soon as I can. Give it a try!
Honestly, Daikatana is not as bad as a lot of reviews have led me to believe. There are a lot of moments and a few stages that I would call pure BS, but I still had a good bit of fun with the game despite all of that. I like that you can improve your stats. I ran into a pretty nasty (and infamous) crash partway through the game and had to download patch 1.3 to get through it, but I don't hate my time with the game. It has some really neat ideas and Superfly either clearing his throat or doing his best Ahnold impression always made me laugh, but man I can understand why it might not be someone's cup of tea. If you're going to pick it up, do yourself a favor and get the 1.3 patch. It'll save you a lot of headache and add a few quality of life improvements.