First, additional bills of rights for the modern era:

1. Right to bodily autonomy (including medical autonomy)
2. Right to privacy (online data, right to be deleted, right to be anonymous online) - this would render the Patriot Act unconstitutional
3. Right to online speech (applying 1st amendment to online public forums)

Second, place some limits on existing things that have gotten out of control:

1. Curtail the power of the administrative state and restore congress as lawmakers as opposed to unelected bureaucrats
2. Restrict eminent domain to prevent property acquired through eminent domain from being transferred to private companies
3. Amend the commerce and tax clauses to remove the quasi-police power granted to the federal government during the post-Lochner era - this would render Social Security and Medicare unconstitutional which would fix our budget crisis
4. Reduce the ability of congress to pass omnibus bills i.e. something like a one-bill one-purpose rule
5. Amend the war powers clause to re-enshrine that Congress is the body that declares war.
6. Amend the Treasury Clause to render the private Fed unconstitutional and re-enshrine the Treasury as the sole body that is permitted to control monetary policy and print money

Third, limit corruption:

1. Ban the revolving door of public official later working for private enterprises that they were supposed to be regulating i.e. 5-10 year prohibition on working in the same private sector as you were working in government
2. Reorganize federal presidential elections to occur during a much shorter time-frame

Fourth, correct existing amendments:

1. Repeal the 23rd amendment and abolish the District of Columbia as being a separate entity from the states - can be placed into Virginia or Maryland
2. Amend the 26th amendment to be 25 years old i.e. the age your brain is fully developed