I'd say make the highlight a bit more saturated/noticeable? Red is a nice color to indicate danger, though I don't know if that would break the atmosphere. Another thing is the object itself - I think a lot of people can agree that first instinct says that a spider is an enemy and a tree is an obstacle, not the other way around. Although I do like how the spider obstacle moves... I hope this helps! If not, that's cool haha, this was the best I could come up with