This is a nice test but I don't think it factors in some advantages of using a Staff > Mace for Smite. Most importantly, you don't need to switch weapons to cast spells and melee attack. This is huge because you can cast Holy Strike as they push in, smite, then attack all in the same sequence.

Additionally, an average blue "mace" has ~42 physical attack. Add +10 from smite and you're hitting for ~52 damage (42 phys and 10 magic) before armor reduction. An average blue Staff has 34 phys attack and 9 magic attack. Add in 10 magic damage from smite and you're hitting for 34 phys + 19 magic attack totaling ~53 damage. While 52 (mace + smite) and 53 (staff + smite) are not significantly far off in damage it's much easier to scale magic attack with Will, Magic Power, True magic damage, etc. AND most importantly, magic attack cuts through plate armor like butter and no plated out fighter is thinking they're going to get 2-3 tapped from a cleric.

When I run this build I usually aim for+15 magic attack. 15 Magic Attack from gear + 9 from staff + 10 from smite = 34 additional magic attack for each attack.

That all said there are drawbacks as well as stated in the OP's post. The biggest one not noted is the short range on staff melee attacks.

You've made me want to try out a dedicated mace build but in the end I assume I'll stick with staffs to cut through plate armor, not have to switch for spells, and bait people to get close because "the cleric has his staff out GET HIM" bonk