I have a note to pre-designed platforms for turrets, like the last dreadnought tower with superfiring barbette, yamato tower with lots of platforms for secondaries, russian pre-dreadnought hull with side mountings for secondary turrets, even casemate gun cutouts... should be invisible , meaning hulls modelled seamlessly without them, no platforms showing and no holes in the hull for casemates, until you actually place something there. Anchor points would be informing you that there is a platform available, or make them semi-transparent, showing only when the player is placing appropriate turret/gun.
Now it just forces you to put something there or live with those gaping holes... which looks kinda weird.
Not to mention that those towers with baked-in barbettes dont handle 17 and 18 inches and you are just wasting space or are forced to take less advanced tower.