Major: Here's what people seem to miss when they are promoting companies as the best (or only real) option. A lot of customers do want to know their writer and be almost like "friends." It's true that they might not want to be friends on Facebook, because of the privacy issues you mentioned. But they want to be able to reach the writer immediately and discuss things in a detailed way if necessary. It's a trust element that isn't adequately captured with discussions of the BBB and security certificates.
There have been times when I couldn't take something on, and my only choice was to refer the customer to someone else. The customer often says: "I want an individual writer, not a company. Do you know anyone good?" I guarantee that those customers would not be impressed if I put them in contact with a company and promised that it had X, Y and Z security protocols and was a member of the BBB, because that's not they want.
On the other hand, I'm sure there are also students of the opposite variety, who only want to deal with established companies. But those aren't the types I've tended to deal with -- they don't get in touch with me in the first place.
What I think would be useful is to get involved with the messaging apps that college students tend to use. Then you can be available and in touch in a way that's relevant to them, and they can maintain privacy.