I have four of the expansions purchased. As many times as I have played, only two expansion side quests have come up, with only one of them showing up more than once. Is this going to get fixed at any time? I have tried to trick the game into giving me a new side quest numerous times (starting and stopping campaigns, skipping whole campaign missions to see if I get one). For now, I am not purchasing any more expansions until this gets better because it feels like such a waste of money for an entire set that never fully gets used. And if anyone really needs to ask, I did add them to my collection.
On a side note, I really think most of the perils are a great idea and presents a challenge. Well, except when there is a hard boss fight and both characters need to split 14 damage between them.