Unfortunately Brown's defense seems farther away, and his biggest offensive strength (driving in a straight line and getting fouled) is one of the least likely to translate rapidly to the NBA, as we've seen with Smart.
But we have a good team and a deep bench, so with any luck we will have a few garbage time minutes here and there for him right away, and lots of quality guys around him when he's on the floor. And if he plays his way to something more, all the better.
I don't think Smart's path is any reflection of how we should expect Brown to go when it comes to the driving game.
Smart doesn't have the athleticism to give him an edge over the average NBA guard. He struggled finishing over length even in college, and everybody knew he may lack the speed to blow by NBA defenders.
Brown's size, speed and leaping ability make him a LOT harder to keep out of the paint.
I dont like to use this as a measuring stick, but if you look at smart in summer league, he wasbt exactly getting into the paint (and to the line) at will. Brown got to the basket at historic rate, and even if he struggled to finish at the basket his ability to get to the line largely made up for that. If you can gey 17 free throw attempts in a game, you can afford to miss some layups.