Thats definently the proper way to upgrade the turbo, modifying both the compressor and turbine. But its still the same issue, that your pushing more power through the same hole.
For the all time spent modifying the stock turbo, how much more costly would it be to just simply upgrade to a turbo that has a more capabable compressor and a proportionant turbine housing to match.
I know there are circumstances where replacing the the turbo is not as feasable then upgrading the stock, like say in instances where the turbine housing is casted directly into the manifold (like the SRT-4) so that replacing the turbo mandates replacing the manifold as well. Or maybe like some of the mitsubishi's that were reverse rotation and thus it could be hard to replace with an off the shelf. But that turbo shown looked to be a standard 5 bolt turbo, they are not hard to come by.