Although not directly related to BA, I'll be using avios and booking this through BAEC. My choices are YVR-JFK or JFK-YVR with Cathay (I believe this is almost daily) / LAX-JFK or JFK-LAX with AA (3/4 flights a day). Without status I'd like to try any of these First class products across North America. These flights are all 50k avios plus a few dollars.

Bearing in mind the flight times, with some flights being overnight (this will of course save the cost of a night in a hotel, but I can imagine it might be a case of lights out and expected to sleep) and also departure/arrival lounge access, does anyone have any recommendation for the best overall First Class experience? I'm very flexible on my trip and can do any of the routes mentioned above.

Hope this is the right forum to post this, and thanks in advance for any advice.