I don't see all third party stuff as infringing on IP, because there are some third party products that are licensed (ex gokin, for example, who do some superb work but at exceptional prices), and Hasbro are seeking to license third party producers who distribute their product through Shapeways (have a look at the MLP stuff that's already there). Takara do the garage kit licenses, so I'm not entirely convinced that third party producers couldn't make an effort to seek licenses.
And there are plenty of third party products (swords, guns, etc) that are compatible with transformers (eg 5mm handles) and are original IP. I'd much prefer to support new product and new designs than a rehash of an existing character, especially with the diversity of stuff Hasbro makes in the Generations line. Plus as much as we complain about HasbroAU pricing, is still substantially less than third party products.
I'll give you an example. FansProject did their Retro-Future Glaciallord line (a combiner mammoth and other prehistoric animals). They did cel animation style art reminicient of generic 80's anime, and an original box design. I bought it in a snap, and I think its my favourite "third party" product out there. Even the "Scramble-City" style combiner ports didn't infringe Takara IP, because the patent in these has expired and entered the public domain.
Sadly though its not widely available or reissued, so I suspect it wasn't a great seller.
On the lookout for MISB Headmaster Highbrow, Takara or Hasbro. I'm sure I could make you a sweet deal!