1st Will is not a Top 10 actor and I don't think he view himself as that. But he is a talent actor. The fact he has been able to glide through mutiple genre's is proof of this. Drama (Where the day takes you, 6 Degrees, Bagger Vance, Ali, Happyness, 7 Pounds) Suspense/Thriller (I am Legend, Enemy of the State) Sci-Fi/Comedy (MIB Trilogy, WWwest) Comedy (Made in America, Hitch) Animation (Shark Tale) Action (Bad Boys 1 + 2, Independence Day, I Robit). Yes he has mostly done Sci-Fi but he does have a diverse catalog.
Also nothing is a lock to be a Blockbuster, Will studied patterns but that doesn't mean he was going to be a success. The reason he is a success is people LIKE Will, He's just a likable guy. He's someone you would want to hang out with or if you saw on the street you would say what's up. Fresh Prince the rapper and the show is why America and the world fell in love with Will. He's got Oscar nods so people need to stop acting like he only does Action/Blockbusters cause he does it all, you can't put Will in 1 Genre. But Denzel is better than Will, Leo might be slightly better but that's cause of the directors he works with.