It depends on how that country is formed, and what happens to Jerusalem.

If Israel withdraws from west bank and Gaza, and truly allows them to be a sovereign state(s), with their own navy, air force, ground force, then the US would step in via the UAE. I would also guess that they will get lots of money coming in from other Arab governments because they all want influence in Palestine, in addition to money from Arabs as people.

In terms of government, if elections are held I assume Hamas would win (in Gaza and wb). In which case countries like Egypt will start being less friendly towards Hamas than they are right now, because they can be seen as a viable government. The reason Egyptian government would dislike Hamas is because they are a spin-off of the brotherhood, which the sisi couped in order to gain power. Generally, Egyptian government is very afraid of the brotherhood and will root them out wherever possible because they are often the only party (other than police and military) that may be in a position to rule the country.

In terms of long term economy and how the government would function I have no idea. Hamas controls an area the size of a small town, and the Palestinian authority has no real autonomy, its not even allowed to collect taxes. My guess tho is that it will resemble south Africa in terms of infrastructure (garbage).

I don't think it will collapse like Libya and be run by criminals, but it won't be as prosperous and safe as many of the Gulf countries.

Basically I'm talking out of my ass, there's really no way to know