... is the transverse curvature of the main deck.
Of course this is faint, about .3mm at 1:700, double in 1:350 but highly visible and faaaaar more visible than those false and oversized hullside plating.

AFAIK, only Dragon Bensons and some Flyhawk did have these features.

In the past, when kits were cast from an ol'way master this lack was understandable because difficult to handcraft.
Now 100% of masters are 3D designed this is but an easy way, so NO EXCUSE.

Even on large ships, hull sections show these curvature : destroyers, cruisers, battleships and even carrier which have a hangar integral with the hull. HMS Ark Royal, IJN Hiryu, etc DO have a transverse curvature. 10cm center raise on Hiryu for example.

So pleaaaase, give away those stupid hull plating and (re)introduce the deck curvature, making elegant ships.

(I'm here speaking of ships up to the late 1940s)