Imho the iPad is the king. If not for work I could arguably get by with just an iPad/no laptop. When either working or lounging at home, iPad is so convenient no matter in bed, on the couch, chair, laying on the carpet, at a desk, sitting at a bar, on the go. That handiness, to me, makes it so great to use. IME something that is easy to use anywhere has a better chance to be productive. But the thing is, while a laptop has slimmer use case IMHO, the use case for it definitely surpasses iPad. What a laptop does it does at the highest level.
I hate to break your bank but an iPhone-MBA-IPad will be the most productive if your college user takes advantage of their interop capabilities.
But whichever device you go with, my two very highest recommendation for a college student are (assuming you will buy Apple): 1, buy the AppleCare+ with theft and damage protection. I rarely buy it but a college student ummm

. Second, pay the 99 cents or 1.99 for the iCloud back up space. There will be no “my dog ate my homework” or my mba/iPad was stolen or broke. The iCloud backup will have what ever the student completed and will be accessible from the iPhone to print.
Best of luck