I think the proper response to illegally obtained evidence, is to allow it to be presented as evidence, but charge those who obtained it with whatever crimes made its obtainment illegal.

The problem with implementing this in the current system is that the government has a monopoly on prosecuting criminal charges, so that agents of the government can get away with criminal acts. If ordinary citizens had the same power as district attorneys to seek indictments and prosecute criminal charges, it would provide a huge disincentive for illegally obtaining evidence, and many other government abuses.