I think you should have had the sun shine through between their lips. Maybe leave some space between the two as they kiss. As is my eyes want to go towards the sun and not their kiss.
Interesting idea, the flare from the sun is pretty intense though and is causing some weird effects on their faces that prevents me from liking this more. I'm also distracted by the weird stuff to the right (and behind her head).
Sorry, not particularly fond of the flare, I think this idea is good but isn“t really working this time, just that the sunflare seems to be the main focus of this shot and not the couple. I would also try a different composition next time or crop the photo as the sun is in the dead center of the shot and the sign and whatever that is in the right side of the photo is pretty distracting. Just wanted to explain why I only gave this a 3 but like I said, I like the idea and I encourage you to explore this some more.