I'm not sure I agree with all you've indicated. If I'm an employee for a Federal Agency, doing my job and not at a senate confirmation level then my information should be redacted in FOIA. If there's criminal issues, the DOJ and Judicial process has ways of extracting that. The current Judicial Watch lawsuits are showing how that works. Are agencies deliberately blocking FOIA? I think in a lot of cases, yes especially when it deals with some high profile political issues, IRS, State Dept. but that's why we have a process and courts. As far as information the gov't is collecting on us, there is a political process to address that. It's called an election.
If people in this country don't like how things are being run they have the ballot box and SCOTUS has affirmed in numerous cases that certain decisions are political and that requires the people to elect representatives who do what the people want. Does that work? Not in practice when almost 80% of congress is re-elected every election. That's where the corruption comes in, the obstruction, the pay to play, the runaway spending, legislation getting passed w/o reading it. FOIA wasn't meant to be a cure all for people sitting on their asses and not voting and holding elected officials accountable.
As for the FBI, shit who cares? The DHS has my fingerprints & my background and that's so I can fly on an airplane. Does it violate 4th amendment? I'd say yes but SCOTUS has said "we're good with it" the laws haven't changed and until then we're all getting tracked one way or another because "terrorists"