We should split current cops into Law Enforcement (detectives, active scene response), Public Protection (traffic cops and patrol cops), and Local Aid (wellness checks, non-emergency response, non-criminal response). All need to be different agencies, only LE should be armed, and abolish SWAT.
Professionalize it. Standardized uniforms, standardized training (none of this wolf warrior bullshit), clearly defined responsibilities, outside non-LEO internal affairs bureau. They have to be visible too - you should need a warrant for an undercover investigation, and no black text on black cars.
Ideally these could be state-operated instead of local jurisdictions prone to good-ol-boyification, but that might be too big a bridge even for this fantasy.