I think the OP has a very limited idea of drama. Drama need not mean certain destruction. Mystery is dramatic, and there's plenty of that. Moreover, there is still a very real chance of unmaking existence.

To start, if all the gates are destroyed in the struggle, the Gods may unmake the world. If he Dark One's plan succeeds, his endgame may well be the unmaking of the world, so that it can be remade with a Goblin voice at the table. If the snarl is released, it may or may not attack creation. If Xykon successfully screws Redcloak (a very real possibility as he's often shown to be smarter than he seems) who knows what will happen. If Tarquin succeeds, he has an arcane and a divine caster as well, and we can only guess at what he'd do if he could control the snarl. And then there's the IFCC...

Moreover, waiting to find out what MITD is, waiting to learn the true nature of the Snarl, of the Dark One's plan, of the world inside the Snarl, etc., is all very tense and dramatic. What more could you ask for? You want a more simplistic plot?