_eye contact: Does not matter to me. If she's looking at me, that's great. If not, it just means her attention is completely focused on the task at hand, which is hot in its own right.
_help with her hands and/or her boobs. As a rule, hands-free is particularly awesome, but there's nothing wrong with hands PROVIDED it doesn't just turn into a handjob with some oral contact. I've never personally run into that, but I see it in videos all the time and it drives me batty. Tit-fucks are always welcome.
_playing with your balls. I can take it or leave it.
_focusing mainly on the tip. Great as a chapter, but it can't be the whole book.
_down on her knees. The best.
_reciprocity (69 position ) Giving or receiving is best done with your full attention.
_cumming in her mouth/chest/face. Mouth is out of this world. I actually prefer spit to swallow, for some reason. Chest is also great. Facials are not my thing. That's just messy for the sake of being messy.
_a little bit of biting. Not a fan of teeth when my dick is actually in her mouth, but biting the shaft from the side, top, or underside is good stuff.
_licking and/or fingering also you anus I've no experience to call upon with that one.
_dirty/flattering comments or moaning Yes, please!
_deepthroating, gagging, choking. I've never been deepthroathed. The occasional, incidental gag/choke is kinda hot, but too much kills the mood.
_anything else (please be specific ) Including some licking up and down the length of the shaft is pretty killer.
There's no set answer to the length of time. A really intense quickie is every bit as good as a paced marathon.