While I haven't run either of these adventures, my plan was to provide a few comments and design ideas I realized while reading through them. First, The Enemy Within.
I love the layout of the WFRP 1st modules. The module is broken into
- GM advice and travel information
- Political structure
Cover of the Enemy Within! So gorgeous!
The adventure (PCs are mistaken for someone and tracked by bounty hunter) is rather lackluster as a "main plot". I would much rather use something like this as the "B Plot" that crops up time to time and makes the PCs lives more complicated. A lot of this adventure requires the PCs not being able to catch the bounty hunter or some degree of distraction to make it really work (the PCs aren't supposed to figure out why the bounty hunter is hunting the mistaken identity).
It is, though, a great example of a how to run that kind of sub-plot. I've had a hard time pulling off multiple story lines with different weights simultaneously. What is happening in Planescape right now is that there are essentially two main goals: find the receptacle of modron knowledge and destroy the Ring of Lot-Var, both in the Mines of Marseillan on Acheron. Though the ring will need to be recovered from a different plane first.
The emotional weight of both these plots are approximately equal. This adventure provides an example of how to write a low emotional investment adventure that can act as a great way of annoying the PCs during an important moment. For example, the PCs might be trying to sneak in to some temple when suddenly hired arms attack them for some completely unknown reason. Or the bounty hunter has some kind of trap set up from them in their rooms at the inn when they really need a long rest. This might even be a great way of including some amount of faction or political group intrigue without getting in the way of the main story or thing of interest.
This is something I'm going to try and include in a future game.