The Quorn chick'n cutlets are really good, but they're made with eggs, so obviously they're not vegan. That said, they're great for basically any dish you'd use chicken for.
Also, vegan sausage is healthy, and basically one of the only substitute meats that are suitable, since sausage is just filler and spices anyway. I mean like the crumbly kind you can throw in a skillet with eggs and peppers. Worth a try!