A very real problem with limiting citizen suits is explored by Rich Miller. The Illinois Supreme Court has stopped a citizen suit to recover state money spent on G-Ry’s election campaign. This is especially relevant since Daniels will be indicted probably after the election for similar use of state funds and Madigan is under investigation.
The more important point is, citizen suits are a check on government. Federal suits have limited standing, as this case essentially echos, but limiting the ability to sue limits checks on the powerful. This is exactly the principle that Bush is trying to subvert in both forest fire reduction and transportation projects. Democracy is often slow, but that is okay—the process is the point in democracy.