Plenty of legroom in front of 19F, and since you're on the redeye, it should remain open (on daylight flights, passengers sometimes congregate here).

You'll have a middle-seat companion for sure, but you'll be delimited from them by the fixed armrest. You can lean towards the fuselage to sleep, but will need pillow/blanket to take up some space between you and the window. It may get pretty cold by the exit door.

I personally prefer the space of First, even though the Hawaii-route 757V doesn't offer anything like a first-class experience. I fly this route often, but you will never see me in coach.