so is it better to stay with one Grand Company?

If the fee company is allied with a certain grand company opposite of your own, does it matter? How can you increase your free company alliance to other grand company?

Not sure if anyone knows this but are the new jobs going to have a soul crystal to equip? If so with the new jobs you level any base class + job? Or do the new jobs transform u to a new class starting at x level ( level lower than 30 but greater than 1)