Players generally live in West Quad or South Quad as freshmen (although I’ve also seen some at others. I saw Mario Ojemudia and various OL when I was living in North Quad, but that’s a sophomore / junior only dorm). We don’t have any athlete specific dorms at all though and as @kturnup said, most of the athletes (and most of the students in general) live off campus after freshmen year. All the basketball players from my time at Umich (2012-16) lived in luxury high-rise apartments after freshmen year.
Pretty much all of the older U of M dorms have undergone major renovations recently and are thus very nice. East Quad is very nice. South Quad is very nice. North Quad is a new building and is very nice. Everything on the Hill Campus (minus Markley which is a DUMP) is nice. I haven’t seen West Quad since it was renovated. As far as room size, they’re all fairly standard cramped 2 person dorm rooms for freshmen. The sophomore dorms tend to give you options for nicer single rooms or quads with a common area.
It wouldn’t surprise me if boarding schools like IMG Academy, had nicer dorm rooms than freshmen year Michigan dorms since those are built to recruit athletes and our dorms are not. There isn’t a Wildcat Lounge or special athlete dorms.
Edit: Picture of a 2 person South Quad dorm