first, there's plenty of documentation on the
project home site about the roles and how they work. second, it's still a weighted average rating for the attributes, and while it may change per role, the end rating for each role is relative to the population. you can still tweak each role individually as you'd like or create custom roles.
third, the game doesn't provide you with any indication whatsoever on who may be best for a job, however we do know (see the wiki) that skills and attribute can affect jobs. we also know that some jobs may be affected in different ways by traits (ie. rage for military, compassion or whatever it is for doctors). it's still subjective, which is why all the different weights are there to allow players to decide what makes up a good rating.
you bring up an interesting point about taking each component and valuing them equally. i don't know if it's necessary, and i also don't know how much of an impact it would have on the rating without doing some testing. as they're ranked relative to each other at the last step, i don't think it's going to make a difference in the rankings.
finally, no offense, but if you don't want other people chiming in on a
public forum perhaps private messages would be more suited to your needs. personally i like to hear that for some people the roles are intuitive and they've got no problems as much as i want to hear the concerns of people who think it's totally inaccurate.