Weapons being locked to jobs is not a bad thing, what they should do is add a more variety of weapons to lock to said class.

For example, hopefully at R50 a Gladiator can pick to be Paladin or Warrior: Paladin would equip swords, maces, daggers etc and a shield, Warrior will equip two weapons (Dual Wield).

Archer for example will be able to pick between Musketeer for Guns or some other long range weapons depending on the path they choose. That would solve the issue of classes being locked to weapons.

As for how the "Jobs" such as Paladin are acquired, I think there should be specific skills and abilities you should equip before it is unlocked and you will start at 50 but the max lvl for these "Advanced Jobs" can be increased to say 75.

For example, Gladiator gets ro R50, to unlock Paladin he will need to equip Cure 2 and maybe some other skills so to become a Paladin you must have GLA at 50 and CONJURER at 30. Once the required skills are equipped you become a paladin and you can then rank up to 75 to learn new Paladin ONLY skills.

Another example, to become a Warrior, you will need GLA at 50 and various attack skills from the dual wielding PUG. So once you have R30 PUG and R50 GLA you can unlock the dual wielding WARRIOR at R50 and rank that WARRIOR up to 75 to learn new WARRIOR ONLY skills!