Gave GM Mode on NBA2k15 a crack last night.
It's times like this that I wish EA never got exclusive rights to the NFL.
This is the most in-depth GM mode I've played in any game (besides Football Manager on PC)
You can converse with everyone in your organisation. Eg, Assistant GM, Finance guy, Scouts, Head Coach, Fitness guy, all players.
Set prices for tickets, parking, jerseys, etc. I know Madden has this, but there's actually more of a point to it in 2K. As well as having on court objectives, you need to meet business objectives too. My current goals are to sell out 15 games, and make a certain profit over the course of the year.
I've set the ticket prices a couple of dollars lower to encourage more people to come, to get the sellout objective. On the flipside, I've raised concession and jersey prices a bit to balance it out a bit. Once I have the sellouts, I'll fiddle with it again. (then change some prices

)
So started with the Houston Rockets. Start on Rookie, 3 min qtrs, sim qtrs set to 3 mins so the stats match up.
Was 4-0 after the first 4. I won all of them comfortably, so bumped the difficulty up to Pro. First game took Miami to OT, and won by 4 points.
The next two games were against San Antonio and Golden State. Lost both of those. OT in the first one, smashed in the second. Gonna leave it on Pro, because they are good teams. If I get smashed by terrible teams, I might look to bump it back down to Rookie.