When I'm traveling alone on a business trip, I really prefer the UA first suite. It is great for working and privacy. I also find the fully flat bed extremely comfortable.

However, since you're on your honeymoon, it is unlikely workspace is your main concern. Agree with others that the LH seat, while not a fully flat bed, is still extremely comfortable. Also heartily agree that food and service is enormously better (probably not a strong enough term) on LH compared to UA.

If the award allows, I'd follow the suggestion to take UA over on the night flight and LH coming back.