Education? Your own private schools have been proven more financially efficient.
Millitary? Well they could stand a (10x) budget cut.
Fire service? Run by insurance companies as co-op.
Police? Security firms come running faster when your home alarm goes off than police. Cut down the force so they can conveyor civil arrests to the courts. Make reasonable self-defense law and weapon regulations.
Trash collection? Let the HOA/equivallent handle it with a contractor.
Health service? The current insurance scheme is technically nice, only the insurance companies are noncompetitive/under-regulated.
Social security? Mostly see above, with a backup plan from gov for heavy cases - proper labor regulation (in quality, not quantity) would ease the load, at the cost of corporate margins (boo-fucking-hoo!).
Prisons? Need heavy reform - social reintegration, not (only) punishment. Keep them public.
The rest? Keep it government.