Thanks for the support Daft Mugi! Glad to have another awesome fan, and so happy to have another FreeSpace enthusiast! These HLP guys sure know how to keep the spark of fandom alive.
I don't have Thief 2, but I can look into it if people think the content would be sufficiently spooky. I'm also looking into the best way to get my hands on F.E.A.R. again, but it only comes in a bundle with all the games from both the original developers and the publishers (at least I think that's the two involved parties). My understanding is that Extraction Point and Perseus Mandate are the "proper" sequels. It's only $8.50 for 6 games until October 6th, so it may be worth getting. I'm suspicious of how viable the "Ultimate Shooter Edition" on G2A is given it seems to be a package no longer supported on Steam.
After some spoiler-free peeking at remaining "Acts" and "areas/sections" by room name in a Walkthrough table of contents, it seems that I may be roughly 1/3 of the way through Amnesia already, so I probably have 2 more streams worth of it. I want to be sure I have something to follow-up with though, so I'd like people to try to agree on what they think would be a good follow-up to Amnesia. I know it's a hard act to follow, being my gold standard for good horror, but I believe in you guys!