I find pretty much all of the uber-weapons to be quite silly and wish that I had just banned them from my campaign. There's simply no need for them and they put weapon users on even higher footing, damage wise, than casters.
What I'm actually planning to do for my next campaign is have the uber-weapons not freely available, but instead just show up as occasional masterwork loot, with no additional proficiency required. (It's already a low magic campaign with limited access to magic items).
So you can't invest feats in a Fullblade and buy one in town - but you might find one while adventuring, and anyone who can use a Greatsword can wield it. Same thing for Superior Implements - you can't specialize in a Dragonfire Wand, but you might find one and unleash fiery death with it.
It gives a bit more ability to customize loot without having to make sure you only provide the weapons and implements the PCs are specialized in. We'll see how it goes.