The thing about x-world is that it will balance economies over the long haul across servers. This is probably for the best overall, because big and small servers had issues when it comes to gil. Items can be cheaper or over inflated in certain cases due to server population size. If its expensive on your server, going to another to get the same item would be in your own interest.

It will also, in theory, balance out server populations. If your server is over populated and you cant get things like a house, moving to a lower pop server might be better for you or your FC. Particularly if you can still move about your datacenter, there becomes less a reason to stick to a particular server in favor of smaller/less populated ones.

Not sure about he server lag issue. Giving priority to people who have it as their home server does make sense though.

The hunts thing is a matter of just joining player made discords that track this stuff (which already existed). I GUESS if they really want to balance that issue out, they could have it where when an S Rank spawns, there's a 5 minute window where people who are OFF SERVER cant attack it, but on server people can. Once it's been attacked by on server people, however, anyone can attack it, regardless of that timer.