Buff Last Whisper to be a true end game item.
As of now, Last Whisper is a game with an end-game passive, but mid-game raw stats.
I think that Last Whisper should actually be BUFFED to reflect how good it is in the end game, while not making it negate all armor purchases in the mid game. Of course, its cost will also have to be... buffed.
Idea:
Last Whisper 
3715 gold
+ 
+ 1065 combine cost
+80 AD
+35% Attack Speed
Unique passive: Deal 10% bonus AD as on-hit physical damage.
Unique passive: 35% armor penetration
Sure, you might think... man, this really messes up the build path for this item. Almost as if it made AD assassins have a much harder time getting LW to snowball harder and making it hard for ADCs to immediately switch to buying LW instead of finishing BT or PD if people start rushing armor. But I assure you this was not my intent. It was only to make AD assassins and ADCs even stronger by making LW stronger for a tiny extra cost.
