Guess I am also surprised I haven't really listened to The Cars much in general, especially that debut. Maybe I figured I've heard it all already, but I don't remember those deep cuts you mentioned.
Glad you liked Goats Head Soup too. Its maybe not one of their absolute best albums but a handful of songs are certainly my favorite Stones ever. "Dancing With Mr D" has a killer groove even though its sluggish and has very muddy production. It definitely makes me think of a bunch of zombies dancing, and years before Thriller.