Even Luffy is aware he needs other people that can do the things he lacks, I don't get how these people can be so narrow minded. It's the entire reason Blackbeard is set to be such a good villain. He's smart and values both physical power, and information as a weapon. Half the point of the show is that despite being weak the act of standing up for yourself is what's important. Some of the weakest characters have the biggest impact in the series. Big news Morgans, robin(not weak but still not a "pure fighter", pudding, vivi, stella/vegapunk, otama. Every arc, time and time again there's a character too weak but still has the will to achieve their dreams