What's so beautiful about taking the classes that:

1) Are the least desirable groupmates.
2) Are generally the most fragile and skill intensive to play well.
3) Tend to get steamrolled throughout the low and midranks.

And making them spend time exploring all over Thera to achieve balance against their most common enemies?

It makes no sense - it favors elitism, info sharing and cheating. I'm still waiting, years upon years later, to hear where the upside to this system is - aside from being really easy for cheaters and really hard for everyone else.