Last night I was looking for possible particle effect resources for my ghosts, and I came across a couple of interesting-sounding quest/dungeon mods. One of these was The Haunted Tavern of the West Gash. I installed it, together with the optional ESP that adds an NPC to give you directions toward the titular tavern. About 2 hours later, I had completed a very satisfying storyline. I consider this to be a model to aspire toward. 2 or 3 hours of content to explore, and a storyline that unfolds as you continue through it, along with several well-developed characters.
For the same atmospheric lighting reasons I mentioned in my post about my upcoming mod, I decided to avoid the use of Night Eye and instead brought several torches, candlesticks, and lanterns with me. I placed the candlesticks and lanterns around the rooms as I came to them, allowing me to see well, but retain the creepy atmosphere.
Also, since I was using a powerful character, I chose the optional "hard version" ESP, and also decided to fight using a tertiary skill. I'm a mage with also high skill in short blade (for daggers), but I went with archery for this one. My archery skill is only 23, though I have a spell to boost it up to 50. This was a good choice, as I found that arrows were plentiful in this mod, and using arrows made the fights more challenging.
The levels were well laid out, with most areas having a little bit of the story to tell. And I really liked how the "treasure room" was set up in terms of how it was used as a reward.
I'm not going to spoil this mod. If you like the sort of thing I described above, and fighting undead, then go play it! You can uninstall it afterward with no harm done, and probably keep the loot as well, though I simply made a special save for this mod and then deleted it when I was done.