The Dink Network

Well, I'm Simeon from the Netherlands and I've been involved in the Dink Community since December 2001. I've released three D-Mods, don't forget to play them

Private Message

Though longer d-mods are often better ones, what is really the minimum viable length for a d-mod? Some d-mods are very short, and are heavily criticised due to this.

There's no minimum you truly need I think, but it's just what the game needs that determines the length: if you have a simple and short story, then don't try to make it longer but make a Romp. If you have a long story with subquests and such, it's a Quest. I'll skip the Epic here

And the criticised D-Mods you're talking about are probably the ones people thought they ended too soon - with what they expected or they think the story could've been used more than the author decided to do.