Did anybody suggest it to you?
2) Government agency should be able to act on the intelligence it gathers. But if that act limits people's freedom without good reason - that agency should be punished for that (cut funding, fire abusing government employee, disassemble agency, send responsible agents to jail - depending on the severity of the violation).
If I'm the only watched, then I would probably lose more than gain. But if everyone is watched then I would probably gain more than lose.
3) I now see where the root of your mistake is. You are assuming, that by giving government more watching power government would become more powerful. But that does not have to be that way.
Let assume that governments need X amount of power to be efficient in law enforcement. Where X = WatchingPower + ActingPower.
That means that if we keep government power at X and increase WatchingPower, then ActingPower of government would decrease. That's what I'd like to see happen: government watches more and acts less (avoiding awkward actions).
Would you prefer to take WatchingPower away from government and replace it with dumb ActingPower?