Real quick question -

[cmanos]

I don't think it'd ever be beneficial to take those feats. It might be fitting to a character concept, but that's two feats that are only ever going to be taken by Fighters, with mid-high level requirements. At level 6, you've probably got a magic weapon, and by level 12, there's not really any reason you're going to want to fight with a bottle instead of your Crazysword +3, for the most part.

Hm.

I was proposing it as a starting point. Feel free to alter

 

[RigaMortus2]

There is the Throw Anything Feat, which will allow you to throw any melee weapon. This still won't help with throwing improvised weapons however.

Then the Hulking Hurler PrC has a class ability called Really Throw Anything, which allows you to throw anything you can lift, but improvised weapons are at -2 to hit.

And as some have mentioned, the Drunken Master gets a sort of "improvised weapon" proficency.

Just to give you some ideas of what is out there...