What about a stereotypical Damsel in Distress type of quest on level 6 (the one with the two dragons and hordes of rakshasa and slaad)? Granted, it's not a 'jump-off' but it could be incorporated into another farther reaching quest chain.......
The sewer proposals sound great. I miss the connection to Skullport. Without it, the sewers are just plain boring and unfulfilling as an adventurer
.
(Toddling off now. For some reason, the brain is not firing on all cylinders and the ideas are not flowing as they ought.)