I. People are free t have a policy preference. They are also free to ban together with like-minded individuals. Just because they have done so doesn't mean they have to expose their personal finances to frivilous lawsuits by every malcontent that disagees with them.
II. Good idea that does not address the real issue. See III, below
III. The reason we have lobbyists is because we have politicians that keep dicking around with regulations. If you don't want to be regulated to death you hire a lobbyist. If you want your competitor regulated to death you hire a lobbyists. If you want favorable, or just non-punitive, treatment in the tax code you hire a lobbyist.
In fact, every vile intrusion of money into politics can pretty much be traced back to politicians passing laws in the name of fairness (tax codes and regulations).
Flatten the tax structure. Prosperity should not be penalized and those who are allowed to vote need to share the exact same tax burden they would inflict on others.
Regulation should be geared towards standardized weights and measures and protection from fraud, force and catastrophic harm. The Article I, Section 8 and 10th Amendment would be a good brake on the current nonsense
IV. See III above. If taxes are flat and regulation subject to constitutional justification then corporations won't hire former pols because it would be pointless.