[Sarinpa1]

Hardcore dungeons in my idea train? They are not only tough, but they also deal more damage.

Also, possibly untouching dungeons, but what about permadungeons that'd work Fire Emblem style? We already have massive battlefields we can scroll through, don't see why we couldn't have these. (Althrough it'd be very nice if party limit was raised in those. You don't want to be hindered by some asshole that's taking their sweet time? Well, don't party with assholes, amirite.)

Edit : To elaborate. They'd be massive battles that'd take quite the amount of time, meaning you cannot rely on food to survive, forcing resource management. Given they could be carefuly tailored to endanger both tanks and mages (And field magic would have to be tweaked in these, or made unusable completely, because idk, structural integrity nonsense, whatever), there wouldn't be a specific build that'd have the advantage. (Aside from probably GS. Because of the massive FP recovery. But they dominate PvE already so eh.)
But Sarin, Power up is a thing.
Haaa, here's where it comes. Much like in the Fire Emblem games, you would have higher rewards according to your SPEED.(Read, amount of rounds) So just sitting back, chilling, powering up and meditating so you never die would be a pretty bad idea.

But it'd probably really require few sets of pre-tailored maps with enemy placement and choice. So it really is balanced. If you look at other games, sure, at some point strategy guides become a thing, but I don't think lack of randomization would hurt this concept.