For the most part, this is a typical Marriott in terms of amenities and service offerings, but there are many intangibles that make the downtown Marriott above average.
The rooms themselves are fairly modern and spacious and, if you can get an upgrade, offer great views of Public Square, the Rock and Roll Hall of Fame, the lakefront, and/or nearby downtown skyscrapers. Service here is incredibly welcoming, whether at the bar or at the front desk. Even the convenience store is decently priced if you want to grab a light bite and relax by yourself in your room.
Just goes to show that details like service can go a long way towards making (or breaking) a hotel stay.