Wondering that myself
The best pen seems to come from dealers that have a bad attitude about their job.
The most counter-friendly dealer I ever saw was a college kid who presumably knew he was moving on to better things. Always showed the burn card, and routinely cut off only 3/4 of a deck from a six deck shoe. Unfortunately, he did move on.
Got good pen from a dealer who was unhappy here, and said he was moving back to Las Vegas.
Good pen from a guy who's probably not crazy about his job. He mentioned once that he was too old to get hired anywhere else, but the casino hired him.
Also consistently get good pen from one gal. I don't know how she feels about her job, but she deals fast and deep.
Of course, the worst pen comes from the new dealers who are trying to do their job right.