I have a thing for tits bouncing rhythmically. Like, not tits flying everywhere when a girl's getting jackhammered... but a nice, steady bounce when a girl's on top, riding cow girl, bouncing up and down; riding up the entire length of the cock and dropping heavily down. That sort of thing. Or missionary when the guy is pounding steadily (more or less, pumping in every half second or so.) Like this:
(1.5x speed is closer to the source)
I also have a thing for colors and sounds. When a girl's having sex on a bed with brown sheets. Earthy tones. There's something primal about it to me where brown matches with skin tones and natural hair colors. For sounds, obviously the squelching of a wet pussy (standard) or when the pussy's so wet that it sounds like pool, haha (an echo-ey plop sort of sound when the dude pounds in.) Another good one's when a girl is getting pounded from below and the girl cums, her body convulses, the cock flings out, and she squirts (that sound!) And complementary to my tit bouncing fetish, I like the sound of skin on skin contact, thigh to thigh, groin to ass... particularly, when a girl is bouncing up and down on a guy.
Lastly, I like the videos where the girl's having sex in front of somebody who's sleeping and tries to keep really quiet. It accentuates all the sex noises, and I love to hear the girl's heavy breathing, trying to keep her moans in and occasionally letting them out. That's pretty hot.