I’m probably biased from growing up in the area, but Troy is pretty terrible (lovingly referred to as Troylet around our parts). It is definitely not a good college town in terms of things to do/see. RPI would definitely have the most “nerds” as you describe though. I think Northeastern has a decent amount, just maybe not as outward as at some other schools (AFAIK, we don’t have an active LARPing scene though there are a few gamer type clubs and what not). I really believe Northeastern is big enough that anyone can find their niche once here, so if co-op appeals to her and she liked everything else I’d pick NU.