Rocky Juarez has some highlight reel KOs (Espadas, Diaz), and he can crack with that left hook, but for the most part, he's dull. On the other hand, Juan Diaz despite (or maybe because) not being too hard of a puncher, is pretty entertaining, IMO, due to his workrate.
Shannon Briggs is the best example of a guy that can really hit but is extremely boring . Wayne McCullough can't crack an egg but is great to watch .
i will throw malinaggi into the mix. can't bust grapes with a sledge hammer, but puts together some nice combinations.
Not sure if we can categorize Calvin Brock as a true HW puncher, but he does have at least a couple of impressive KOs. And the one over Lawrence was very impressive. But he's boring as ****.
I also would have said that the HW version of James Toney was entertaining prior to becoming completely shot.