Being able to sculpt classes is good and all but pointless combination's are in the end just that.. Pointless... Even in FFXI with its limited customization, you don't see people running around as DRK/BST for hnms, or WHM/DRG just because u get to call a pet. Everyone wants this freedom of customization but they don't realize that its the cause of the problem, This doesn't apply to everyone, the smart few will use that freedom of customization to create a effective combination, the other 70% will just abuse it for stupid reasons. Perfect example would be the freedom in gear that currently exists in ffxiv, the smart few understand the benefit of wearing gear the same lv as rank but the other 70% wear gear because it looks cool. Skills need to be limited and classes need to be limited imo;
even now in the game, some customization is just ridiculous... for example take Archer's skill Wide Volley - "Launch a wide-ranged assault, increasing attack power and dealing projectile damage to the target and nearby enemies." This skill can be used on any class, someone explain to me how a MRD,GLD,PUG can do a wide-ranged assault dealing projectile damage with an axe,sword,fist? Or how an Archer can do slashing dmg with skull sunder.