'flavor' ??
IMHO: coil 'size' is fairly dependent on the atomizer used and where/how incoming air is directed towards it.
There is a school of thought that the less 'open space' in a chamber the better the flavor and another where smaller chambers are more flavorful then larger ones.
The 'exotic coil' folks might argue that the 'burst' of
juice vaporized off their coils (wicked into the multitude of surfaces & crevesses on them) provide much of their flavor.
The Temperature Regulated vapers might argue that depending on the juice flavor might need/require a different temperature for the best
vaping experience.
In all, it comes down to coil surface area and temperature for volume of vapor produced.
YMMV.