I need to make 3 more realistic people for a cover

I need to change the 3 current characters on the cover, I want them to be more realistic and gangster concept.
this is for a cover of a mafia game.
personajes.png are the characters that should be made more realistic.
I need to improve the attached image too much > personajes.png

I attach several references of what I am looking for.
Excellent references3.jpg
references2.jpg
references1.png