The patch addressed that to a degree - after patching, you never actually see respawns. It always bugged me in the original release that monsters and bots could appear in a deserted corridor that you had cleared just moments before. They still respawn after the patch, but far more sensibly. As for respawning itself... *shrug* You're one man in a massive spacecraft. The prospect of a secure perimeter seems pretty unlikely. Cleared areas that stayed clear would have felt unrealistic to me.
The mutants seem pretty insignificant when later critters appear. The assassin robots are bastards - robotic ninjas, essentially, with electronic shuriken and all.
Ah yes, Ultima Underworld's "upset spectre named Warren". Damn, that thing bewildered me until I happened to read the credits. A very cute gag. Warren Spector is also pencilled in to run the production of Thief III (and possibly even System Shock 3 - both titles were bought by Ion Storm after Looking Glass died *sob*) so I am looking forward to that possibility.
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