The way they have it set up now is the most realistic way to do it.
Pitcher injury is scary and real and every pitcher has their limits as a result.
Since everyone is playing somewhat competitive baseball in the spring anyway it's the perfect time to have a somewhat competitive international tournament. It'll never be anything more than that nor should it.
And frankly baseball just isn't a great international sport anyway. It's basically played in North America and Japan. Sprinkle in South Korea and a couple of South American countries who could field subpar teams and that's it. The rest of the world, including parts of North America, plays cricket. I think cricket has 5 times the international following that baseball does. Baseball is just barely an international sport.