I think having six teams from each league make the postseason is better than the older formats, whether it was three division winners plus one Wild Card, or the era of the one-game Wild Card.
I’d prefer the Wild Card round to be best-of-five, but I understand why that’s difficult. It would make an already tight playoff schedule even longer, while also leaving the No. 1 and No. 2 seeds sitting around for quite a while.
The NPB playoff format is interesting in that regard. In the final stage of the Climax Series, the first-place team starts with an automatic 1–0 advantage, meaning they only need three actual wins to advance while the challenger needs four. It’s definitely unconventional, but I can see the logic if you want to put more emphasis on winning the division and give lower-seeded teams a legitimate disadvantage. I wouldn’t necessarily want MLB to copy it exactly, but I do like the idea of rewarding the best regular-season teams more than they currently do.