(1) Land Value Taxation and Split-Rate Taxation,
It might additionally prove appropriate for a centralized government to guarantee certain basic civil rights and civil liberties; such as equal protections under the law, like the right to defend oneself in court, and the equal right to sue.
However, it could very well turn out that those are simply the last functions of government which would dissolve, while a Geo-Mutualist Panarchist system emerges out of the unentangling last vestiges of a constitutional republic. And that goes whether it's a minarchistic one that's decided to embrace true liberty, or whether it's a corrupt democratic republic that ceases functioning or collapses (in any given imaginable scenario).
Edited on January 19th and 29th, 2017, and December 1st, 2018