You were going to run every single one of those big lineups right off the court.
Respectfully disagree. 
Your team is the only team in the league that gives me pause over that statement.
The best equipped team in the league to handle that former Dallas team. With your freakishly athletic players, terrific perimeter defense and pair of athletic skilled post scorers.
Not to become a mutual admiration society here, but I thought your team had enough to play that style of ball with them, especially with ZBo eating brand's lunch. AK47 is probably the ideal counter to LeBron at the 4 and Galls capable of going punch for punch with Granger.
Yes, I think I could've given them a game but ... what I am trying to say is ...
The center I picked up at this stage in the draft was going to be too limited
(either as a defender or an offensive threat depending on who I end up with) to use against Dallas' starting lineup. They are going to have an advantage there and they are going to be able to beat that lineup consistently to the point that I have to go away from it. I have to change to matchup with them and play their style of play.
By moving the center to the bench and promoting AK-47 to the lineup in his place.
They force me to play their game because of the strength of their lineup / style of play. I can't make them go away from it and play a different game. I don't have the horses to do that. I have to play their game.
If I had a better two-way center. Someone who was a legitimate offensive threat (that could punish their smaller defenders) and a mobile above average defender (to help contain their perimeter threats, PnR and provide rim-protection) ... maybe I could have done it.
But I wasn't able to get that guy so my team can't force them away from what they do best.