Originally Posted by
Yora
The first thing to establish is what is the focus of the campaign. Not everything in the campaign needs to be about that focus, but it all needs to be in support of the focus.
A megadungeon campaign still can has a town. In fact it should have one. But the things that players are doing in the town should have a meaningful impact on what they will be doing later in the megadungeon, All content should in some way bring the players closer to their goal. Be it gaining useful knowiledge or preparing for upcoming challenges. However, becoming stronger so that they can fight the monsters ahead is not making progress. That's just plain filler. If the players are in a position where their characters are not powerful enough to progress further, then it's the monsters that need to be made weaker. Not the characters who have to go doing busywork to get stronger.
Progress has to be narrative progress, not mechanical one.