Different formulas have been successful. When the Red Sox won in 2004 and 2007 they had elite hitters and good to very good, but not great, starting pitching.
Some teams have slugged their way to titles like the 2002 Angels.
But in the postseason the balance usually tilts toward elite pitching, and this postseason we have really seen pitching dominate.
Overall the balance in baseball has tilted toward pitching the last few years as runs scored have steadily declined. I wouldn't be surprised to see Selig make some sort of rules tweak to increase scoring, similar to what was done after 1968, because I think TV ratings this postseason have been hurt by the low scoring. We all like a good pitchers duel sometimes but a steady string of 2-1 and 2-0 games gets a little boring.