I wish they would just put the elemental wheel back into the game, give BLM (among the other classes) their old spell list and that would be that. One Garuda abuse and they rip it all away...

I do like the idea however of a class/job that actually uses all the other classes. Regardless of what they're trying to do now, the very absolute core of this game is to level several classes and jobs. Yes the original intent was to combine it all, which didn't go over well as a whole, but theres no reason to make good use out of a very valid option, for the more hardcore players.
I get the reasoning behind trying to stray away from it (same reason they took out the elemental wheel all together), they didnt want class favoritism (a silly notion, there always will be). However again, theres absolutely no reason to give a valued Onion Knight class into the game, as long as its not overpowered to the point of demanding every player have it to join a party.