[Dixielandjazz] Hypothetical question

[Ken Gates]

Maybe this question will spark some interest.
Let's say there is a 7 piece OKOM band with conventional front line of
three instruments and 4 piece rhythm section.  Each player is of satisfactory,
but not extraordinary skill level   If ONE player were to be replaced with
a person of the very highest skill level, which instrument would make the
most difference in the upgrade of the collective sound of the group?
A member of the rhythm section?  Of the front line?  Which instrument?

I'm wondering if my choice of --- string bass player ---is shared by anyone.
Seems to me an upgrade of the  rhythm section will improve the sound of 
the front line.. Not sure if front line upgrade will necessarily improve the 
function and sound of the rhythm section. 

Any opinions?

Ken Gates