"Tony Kramer is an artist, my guess is he's supposed to be Bernie Wrightson (whom Kramer kind of looks like).  The other reason I think this is because of the scene in v2 #4, where Kramer meets Nick Fontana (Joe Orlando), who compares Kramer's style…"

"Curt Powell is Frank Miller.  That's why the Eastman and Laird stand-ins go up to Powell and thank him for being their inspiration; TMNT was inspired by Miller's Daredevil and Ronin.  You also see this in the one-pager in V3 #3, Curt Powell is at…"