One week you might have 1000s of engineers in town for a conference while the next you have a techno music festival.
For example, most Sunday nights are quiet - but this coming Sunday will likely be crazy with the Lions/Packers game deciding the NFC North on Sunday Night Football. That usually leads back to Greektown based on its location in the downtown core. Your best planning is to look at the hotel/casino as the base for what you want to do in the rest of Detroit. Of course there are dozens of other bars that might be hosting something all the way up to 70,000 or so at Ford Field for major events. You will need to check your dates to see if there is anything going on that interests you. Motor City does have a small theater venue (1900 seats).
That leaves V at the MGM Grand which does not get great reviews. April QAGR by casino was 432,195 for MGM Grand Detroit a negative 1.7 million for MotorCity, and 1.4 million for Hollywood Casino at Greektown. It also looks like Amnesia at Motor City is only available for private parties now.
I thought Greektown had built one, but apparently not. You might find a cover band playing in one of the casino bars on a weekend, but it is hardly enough to keep you entertained for three days without leaving the property. They are primarily about gambling with a side of drinking mostly frequented by locals. They are all roughly the same - and boring when you come right down to it.
