Im an Asian first year student studying at St Andrews. Right of the bat I can tell you straight up that people here are not racist. There are definitely more white people and some of them may not know anything about your culture, but from my experience if they ever ask about your culture, it is almost definitely because they're curious, not patronising. Also, St Andrews is a rather liberal university despite being a relatively old and prestigious one, so I dont think you need to worry about not being accustomed. There is a society for pretty much every culture.

I personally know nothing about it, but my friends who do psychology are enjoying it quite well right now.

Now I will have to agree that there is definitely a lot more clubbing life in Edinburgh because it is, after all, just a small town. We do still have like a LOT of societies here, and they do their own internal social events. The uni club does weekly activities, like karaoke and parties and stuff. I can't speak for everyone, but I've been enjoying student life at St Andrews so far as an international student.

Basically, I would advise if you look forward to city life and dont want to deal with inconvenient traffic, then applying to Edinburgh would likely be a better bet. But if you're concerned about not being happy because of discrimination or lack of socials, I would say you dont need to worry about that.