(Dragon Ball fan here) Don't try to replace Bleach in the Big 3 with Dragon Ball.

The Big 4 was created for a reason. It refers to general popularity and impact, regardless of time period, and therefore includes Dragon Ball. The Big 3 is based on manga sales and popularity at the time as they all came out within a 4 year span and were all in Weekly Shonen Jump. So they naturally belonged together. Yes, Dragon Ball is arguably more popular than Bleach, but it also debuted 27 years before. It is just as great as a series, and when people use the term "Big 3" they aren't trying to discount Dragon Ball's impact, quality, or popularity. The Big 3 and Big 4 just mean different things. Just use "Big 4" when you want to refer to all 4. Otherwise, let the Big 3 stand on its own.