Quick idea to give Essence Reaver a good place

The general idea behind is to allow AD champions who use mana to fire off their abilities a more often without fear of going oom and being a sitting duck.

My suggestion (This would, of course, require shifting around the other stats in exchange): Remove the cooldown reduction, but add a second, stacking passive that increases CDR when in-combat and autoattacking, up to a cap. The item then becomes a great choice when someone expects extended teamfights, pokes, or objective captures. The longer the fight goes on, the more cdr they receive, and thus the more often they can use their skills. It also makes the item slot-effecient, since the player wouldn't have to get several items that give 10% cdr, but on the condition that they stay in extended fights. It could potentially even add another level of strategy where a player waits until later into the fight to use their high-cooldown skills, thus making use of the passive.

Thanks for reading!