I personally agree with Skin_. I don't think any human interaction is really necessary, and I really like the way it is with just the player versus a facility full of escaped SCPs. Being completely alone really magnifies the scare factor, and I think that's one of the key things that's made the game work so far.
If you go and add scientists it makes me think of the beginning of Half-Life 1 - all the talking leading up to the aliens actually invading followed by everyone commenting about how "the aliens are totally invading" and "how did we not see this coming" etc. for the rest of the game.
It's very hard to make them not sound cheesy and to actually add to the immersion, and I'm not so sure the pay off is really worth the trouble. The notes already do a fantastic job adding to the back story, and as Skin_ said, 035 already provides a little break with some NPC interaction. In my opinion that's all the game needs
I'd personally still be open to the idea if there were some more solid ideas as to what the NPCs would add to the game though!
Not that I have any say in the matter anyway, just my two cents!
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