It’s a good start.
But the next thing he needs to do is cut congresses salary by 80% and end their medical and retirement plans along with all non security related government employees.
He has no legal authority to use the Slash and Burn approach you favor. Congress is a separate branch of government is may surprise you to learn and the executive has no power over it for the most part. Retirement plans are established at the time of hire and that is what Congress has approved. The Courts have repeatedly ruled on the right of contract which is inviolable in a country under the Rule of Law.