Honestly, I've never modded the original and I enjoy it quite a bit, vinraith. But then again, I'm generally one for vanilla experiences in my older games.
Nope, bad advice. TFTD ramps up the difficulty significantly, and doesn't really do anything different except add multi-part terror missions which drag on for ages and are incredibly unforgiving due to the tight cruise ship layouts with no room to move. Um, and part of it is underwater I guess?
Yeah, I don't know really. I haven't played TFTD yet, so I was unsure. But okay then!