Aesthetic wise, that's mostly just taste. I find the corridors and steam stuff very fitting for what should be a cramped place anyways as we're only traveling up the arm. A3's boss is actually an allusion to http://finalfantasy.wikia.com/wiki/Liquid_Flame

Also considering the last boss, I see it being a function of Alexander itself, instead of goblin cronies or anomalies like the A3 boss. That's why it doesn't move, and killing A4's boss is basically taking a stab at Alexander itself.

Difficulty wise, normal is supposed to be really easy. Not everybody's skill level is the same, and Savage A1 is supposed to be more simple mechanic wise to get most groups started, just like how simple turn 1 coil was. So I don't know how much you were expecting from the early fights.

Story wise, it is not as epic as Coil of Bahamut, but the threat of a massive primal is pretty real, whether or not you can see it visibly to the land. Instead of sitting on our butts and waiting to see if it actually does something, we're taking an initiative on it.

As far as the raiding system as a whole goes, what exactly do you suggest? Not having story mode out before/during the difficult raid? If we put a wait on that, we'd see a thread just like this but in reverse, about how people can't see current stories and etc.