Firstly: What were everyday clothing options for male students for occasions where a suit would be too formal? From what I can tell (which is again mostly gleaned from comics) is: a hell of a lot of sweaters and blazers, and shirts with ties. Were there any details in this that were used for personal expression? Any sartorial choices that would look a little unusual, whether in a positive or negative way? Anything that would indicate coming from a wealthier or poorer background? Anything that crossed the line from no-nonsense and clean-cut into looking like you didn't give much of a damn about appearances? (Without edging into "unkempt", just not being particularly trendy.)
Secondly, and probably a little more difficult to answer -- this character is of Romani background. It's not something he's extremely secretive about, or which he would actively lie about, but not something he is particularly talkative about, either. I'm wondering about cultural perceptions of this. The stock "gypsy" stereotypes sound like they were fully in place in America, but I'm assuming more distantly for the students of Fictional University, more of the "sell you to the gypsies/gypsies don't really exist" variety. Someone mentioned that he might be assumed to be Jewish, being a European immigrant who doesn't look quite what the time period would consider white. How would that effect how he was treated and perceived, granted that he isn't particularly religiously observant and doesn't talk much about his background? Would this be less of a problem given that he's an engineering student? From what I can tell, NYU (and by extension its fictional equivalent here) had a lot of Jewish students; would there be student groups that might reach out to an isolated new student?
I've done some general research on American men's clothing of the 1950s (and I've also read about the Ivy League look, though I don't think the character in question would care about that at all), "college clothing 1950s", and specific college names + "[fashion/clothing/clothes] 1950s". For the latter question, I was able to find a lot of material relating to antiziganist prejudice and violence in Europe in the time period (especially so soon after WWII and with oppression certainly still ongoing) but not a lot about American perceptions.