I know he's ranked 4 and that but I think Del Potro, Berdych and Tsonga would be the dominant guys if the top 4 weren't around, not him.
Evidently. First and foremost, if the current top 4 weren't around, the courts/conditions would be sped up no doubt leading to Ferrer becoming a non factor. Ferrer's star power is 0, guys like Tsonga and Del Potro are infinitely more popular among tennis fans and neurals alile despite being ranked lower at the moment - in fact Del Potro's popularity is probably on the same league as the current top 4 (bar Federer of course) despite not winning a big title for more than 3 years, which is why there's this perceived 'hype' around him.
Besides the fact that the ATP would never allow even the slighest risk of someone like Ferrer being the face of the sport in any way, he doesn't have the mentality required to dominate anyway (or the game), so it's a moot point.