For most wild shaping options, weapon melding is just a convenience that permits you to keep it even if your new shape has no hands. Years ago I played without this rule (by mistake) and everyone could keep its equipment if the new shape was able to wield it (like for undead anatomy or monstrous physique). It made polymorph spells a bit more powerful but it wasn't game breaking and nobody realized there was a mistake being made.
More recently I made that homebrewed feat:
Polymorph Control:
When you are affected by a polymorph effect casted by yourself or an ally, you can choose any number of pieces of your equipment that are not affected by the spell. They don't meld into your new body nor change size. If your new shape is not able to properly wear them they fall onto the ground
It was mostly designed to make possible the trope of the character with a giant sword he can only wield when he transforms himself. By simply following the existing rule the only way to achieve that is to drop your weapon, polymorph, and pick it up. I find this ridiculous.
On a balance point of view it doesn't really empower any already powerful build. Yes, it means the druid can carry weapons and use them in his gorilla shape, but it won't make him as powerful as if he used the natural attacks of a tiger for example. For this reason it shouldn't cost you more that a +1 (maybe even only something like 1000gp flat).
