Red is one of the strongest colors, it's blood, it has a power with the eye. That's why traffic lights are red I guess, and stop signs as well... In fact I use red in all of my paintings.
It is all very well to copy what one sees, but it is far better to draw what one now only sees in one's memory. That is a transformation in which imagination collaborates with memory.
The real challenge for a vegan is getting vitamin B and omega-3s, but you can get those in a vegetarian supplement.