Dude, you hit it right out of the park with that question. So few know how to swear well and how to talk dirty without resorting to standard cliches. "Oh fuck me! Fuck me hard!" always makes me giggle (or cringe) and instantly makes me feel like permanently moving into the "friend's zone".

I wholeheartedly agree about rating such a skill. If a girl knows how to talk dirty well, that should be noted, encouraged and rewarded.  

I think Yes/No on "Keeps an eye contact during BJ" would be another criteria that I'd add.

A regular would say to me now and then (as my balls are slapping against her) "FK me like you mean it...!"

I was with a regular who usually dirty talks to me during K9 with, "You like that?" "Do you like watching my beautiful ass while you fuck me?" "Do you like watching your big cock go in and out of my pussy?" but the last time, she turned back to look at me over her shoulder while I'm pumping away and she asked, "Your thoughts, if any?"  

I went limp, the condom stayed in her pussy as I drooped out and fell onto the floor, curled up into a fetal position and had to pay for another hour as I recovered.

...

talk, ranging from submissive, to sexy to dirty can be  
an amazing aphrodisiac ... it takes the burden off of  
being completely in charge of the mental aspect of sex.

I personally enjoy a verbal exchange at some level, as it
 keeps both players in the game, even when acted out ... well.