The Lakers Offense does flow through Kobe, you are correct. The Mavericks offense works best when it flows through Dirk. Dirk is, on the Depth Chart, a PF. So there will be times that the ball will go to the other side of the court (Opposite Wing, supporting C) and a shot opportunity opens up before they can get it to Dirk. And that is fine, when the opportunity is there, take it... don't force.
Kobe is a Guard, much easier to run through a Guard. Obviously Kobe will get more touches.
Now, Dirk gets more chances than most Bigs because he doesn't exactly play like a 4 plays and he will spot up on the perimeter quiet a bit.
Kobe is amazing at creating a shot, both driving and pulling up. Dirk is every bit as good at creating the Jumper, moreso due to his Height and Quick Release than Kobe and his ability to make a move and stop then pop. Where Kobe has a much greater advantage is going to the basket, where his ability to drive and then his acrobatics allow him to perform near miricles.
Kobe will also back down smaller Guards... when Dirk backs some one down it's usually an actual PF/C. Even at 7'0" like Dirk is, those Defenders are actual Post Defenders with legit height... so when Dirk backs down it's a Post Player, when Kobe backs down (like MJ did) it's a Guard. One Kobe usually has the Height Advantage on, and one that doesn't know much about defending the post. Still, whether the Post Player against Dirk or the Guard on Kobe... who REALLY knows how to guard either of these guys 10 feet or closer to the basket?
Look, Kobe is amazing. Kobe over his career has been better than Dirk. Where I differ on your point here is that you say Kobe lead his team more effectively than Dirk. Dirk is the Leading Scorer for his team, just as Kobe is for his. If they don't score, usually they don't win. Now Kobe gets locked in, becomes a ball hog. This is sad, because Kobe is actually a very good passer... he just doesn't apply that much. That's a trick MJ learned early, and he made his team mates better by using it. Kobe never quiet got to that level with giving up the rock like MJ did. Dirk on the other hand, even as a PF, will work the rock. Dirk will also set Picks. Maybe this is because they use Dirk on Pick and Rolls and Pick and Screens, but Dirk sets picks off ball too. Kobe never sets a screen.
The Offense doesn't work through Kobe, it is absorbed like light into a black hole by Kobe. This leads to some amazing things like Kobe scoring 70 and such... but also leads to the Lakers losing games that they shouldn't lose because Kobe was hogging and not hot.
On the other hand, Dirk shot 28% in a FINALS Game, and still contributed with Assists, Rebounds, Blocks and Steals... along with the game winning Dunk. So even when Dirk is off, which isn't often, he still helps his team. When Kobe doesn't score a ton AND shoot well, it's a rough night for the Lakers.
I just don't want you thinking I'm giving Kobe 'hate'. He's a Top 50 all time for sure, one of the Top 10 Greatest in my Opinion. But last year, he was not a Top 3 and he was not better than Dirk. This year, especially in a shorter season... who knows? He could be back on top all over again.