I've thought about this and might give it a try soon: An adventure of which you create the plot yourself and takes multiple lucid dreams to 'complete'. This is probably the most enjoyable for people who have LD's often.

The basic idea is that you think of a simple plot while you are awake which you will follow in multiple LD's. Your 'tasks' have to be done at multiple locations and are too much for one lucid dream. You complete one task (one part of your adventure) per LD, and when you've completed your task you will (preferably) be rewarded with an item you need. Why an item? Because it's easier to pull an item from your pockets in another LD than to start where you left of in the last LD. Does everyone still understand what I'm trying to say?

Here's my idea:

My lucid me has heard of a powerful ancient artifact that can boost (or grant) magical powers. This item has been split up into three parts, scattered across the world. I'll have to find these items and when brought together they can be forged into the magical artifact you wanted. Maybe one part was stolen, maybe one part is inside some old ruins? I'm just thinking out loud here.

If you succeed in completing your adventure not only you've most likely had a lot of fun, and in my case it can help increase dream control. Let's say you're having problems in an LD: Magic doesn't work well, you can't fly, etc. Just pull the item/weapon from your pockets and there you go! It was very difficult and dangerous to get your hands on this mysterious item, so you just know it works.

What do you guys think? Fun? Too complicated?