OP, you keep saying that forcing us to play as one job would increase immersion, but the locking is completely not necessary. If you'll look at my pads, it took me a year and a half to get PGL to 50. A few months later I got ARC to 50 just to see if I enjoyed ranged classes (for inevitable MSK inclusion).

Before getting ARC though, when people asked what job I had, I could proudly say PGL. I mained it, it was the only combat class I enjoyed, and it's still the one I associate Llen with the most. Therefore, I argue that locking us to a single class not only ruins any sense of attachment to a character, it actually impedes it entirely. Why let the game tell you what you can and can't do. If you're an intelligent, sentient being, maybe you don't want to be a level 50 Everything. Maybe you want to use only one class. I did, and I can assure you I feel much closer to my character for having done it.