Yes, it's a shame Bo Hopkins wasn't brought more permanently on the show, as I dig his character and his portrayal much better than Rockford's regular contacts, all of who (except maybe Beth) are there to inhibit him as much as help him.
A few of you mention this episode containing a glimpse of David Chase's work on Sopranos. I agree. But I think we have been seeing that on every episode he wrote since season 3. Maybe even season 2. All of the gangster, hoods and hit men are always very well realized and definitely not the normal TV clichés of those types. There is always a sense with Chase episodes that you could follow these guys home and see Sopranos 1970s style.
I notice David Chase also liked to add an awareness of youth culture in his episodes, many of which tend to incorporate something of youth concerns and climate back then, particularly one episode comes to mind when Jim helped the Hare Krishna girl. That episode was scathing of the "Me Decade," while again also giving the sense of characters who really live in that world. Other writers on the show seem more concerned with the mystery hat trick while Chase liked the subtle observation and comedy of his characters.