The idea has some merit, but I wonder if the import/export needs of TX as a country would be fulfilled. The 'United' States was formed primary as a mechanism of order so that our nation and economy could be represented as one entity.for strength in numbers in many aspects and to unify rules and government procedure as a nation of 'laws' on a collective and individual basis.
Being from Los Angeles, Calif, where there are 88 cities in Los Angeles (Calif. being the 5th largest economy for country's - not STATES in the World) I see the independent cities of El Segundo, Santa Monica ,Culver City etc. do better with smaller governments and less corrupted elements that are involved with larger umbrella efforts.
I think the combined protection of the Federal oversight for emergency situations might be oversold, but other than a central bank, treasury and federal laws, I can't think of any other dis-advantages.
off the top of my head without any historical context or research