The problem with doing away with the FBI is the same interstate law enforcement issues that caused its creation will reassert themselves in a big way.
Three prominent reforms that are needed is:
1. No more FBI interview process crimes. If the FBI interviews you, it must be recorded. All records of the recorded audio\video & written interview are given to the interviewee and his\her legal representative. If that isn’t done, then it’s like the interview didn’t happen. The SA & immediate supervisors are then disciplined for not following the rules.
2. Separate CI & CT responsibility from the FBI. Most of the recent problems have been cause by the FBI’s Washington based CI unit. It’s too close to the leadership and too close to the politics of DC. Create an organization that functions like the UKs MI5, it only has investigative responsibility. To make an arrest it has to report to a federal DA and has to meet the federal standards for an arrest to be made.
3. Prosecute the people who corrupted the FISA process.
Sorry, no fixing it. Kill it.