Is it grammatical to coordinate adjectives and nouns as follows?
Steve is a helpful classmate, a good friend, and wise when you turn to him.
I have not come across sentences like that, at least in school; maybe I should say I do not remember seeing a construction like the one below whereby you have a mix of nouns and adjectives joined by a coordinating conjunction such as "and", "or", or "but".
Noun1 is a noun2, a noun3 and adj1.
Steve is a helpful office mate, a good friend, and wise when you turn to him.
Source: made it up