A bit hard to understand what I am trying to get at with the thread title so let me explain. I want to suggest an alteration to the primary and secondary weapon slots where you can have the same shield on both slots or the same weapon if desired. Sort of how the light source slot works. The reason being is cause while using a cleric PC I did find it annoying I couldn't set up a slot specifically for spellcasting but with a shield still equipped. I could do it with a weapon (kind of) by removing the torch/candle in the light source slot and just having the weapon equipped or using a ranged weapon in one slot but plenty of times I would prefer keeping the shield out for the AC bonus and the only way I can do that is manually equipping the weapon from the inventory screen and re-equipping later when I want it back.
It isn't just spell casting either. There was a point where I wanted my fighter to have both their starting axe for slashing damage but also wanted to equip a warhammer as a secondary to deal with skeletons. But cause I could only have the one shield they had in one slot I would need another shield should I want to keep the shield AC bonus.
I would think it would be possible to clone the primary slot in a way that you can do such things. I mean you do it with the light source slot.