You could also cut to events going on elsewhere. Just because the player is in the dungeon does not mean that the rest of the world stands still.
A good idea, for example, is if you have a large amount of cuts to what is going on elsewhere at the end of the dungeon, to perhaps split them into shorter scenes, then add them in so they play as the player progresses through the dungeon.
As far as second play throughs go, there is the system that Breath of Fire: Dragon Quarter used. Clearing the game netted you a rank, based on various things, including map coverage. Depending on your rank, new areas and cutscenes became available, additional story elements that you may not have seen before, or things shown from a new perspective. Clearing the game again, with these new areas, meant your rank could grow higher, unlocking more secrets.
It was a very short game, but one founded on replayability.
A good idea, for example, is if you have a large amount of cuts to what is going on elsewhere at the end of the dungeon, to perhaps split them into shorter scenes, then add them in so they play as the player progresses through the dungeon.
As far as second play throughs go, there is the system that Breath of Fire: Dragon Quarter used. Clearing the game netted you a rank, based on various things, including map coverage. Depending on your rank, new areas and cutscenes became available, additional story elements that you may not have seen before, or things shown from a new perspective. Clearing the game again, with these new areas, meant your rank could grow higher, unlocking more secrets.
It was a very short game, but one founded on replayability.