Recommendation for a small collection, Descent or PaF or other Big Box expansion with expedition.

Hello,

A while back, I had all the content for the game up to the Outcast wave. I sold my collection because it felt overwhelming with too many waves and I stopped playing it for a time. I recently had the itch to play the game again and got New Age and the ancients again since it was my favorite box I previously owned. It's been a blast playing it again, and I would like to get just a little more content for it (I feel like 2 waves is a sweet spot for a small collection). Which gets to the point of the post, I'm wanting recommendations for what other box I should get, specifically the ones with expedition mode. Any recommendations would be appreciated.