Thank you for your answer. I'm glad that most of the points are similar to other feedback we got internally and also from other players. Especially the highlighting part.
For the stress level, I think the major issue is that Plants vs Zombies had, from a narrative point of view, the slow zombies involved. So there's plenty of time for the players to react. It's quite the biggest difference between the two. It's way more frenetic ( and not in a good way ).