it depends on his weight as to how much you give
as for toppings -== if he eats it like it is that should be fine
because that is the way to create a picky eater is to start garnishing the food regularly
he will get use to it and not eat it plain
what food are you feeding? do you have current side and standing pics of your pup and one from above for reference?
oh to answer your question
no he does not need toppings if you are feeding a high quality food