Out of these characters who deserves to be taken the most seriously ?

so it's between the so called weakest character in OP.

Who do you think will make the most progress? Have the most accomplishments? Most feats? Who deserves to be listened to the most when the speak on something serious?

Foxy
Buggy
Chopper
Nami
Usopp
Coby
Vi Vi
Rebecca

Or if you can think of any other low tier character, what do you think ?