I really love the art aestethic on this game. It's bright, but it's still readable. I couldn't get the plague to corrupt my potatoes though, they were all fine at the end.
One critique I would have is I think the intensity of your lighting is too high in order to create the purple effect. I'm not too familiar with Unreal, but it might be better to lower the intensity and then make the colour bright using a post processing effect. At the moment you have a really bright single light source that's eating up the GPU (I think).