While I agree that the kiss makes sense, its reasons make me feel a bit dubious about a true relationship between Superman and Wonder Woman.
They basically both felt lonely and sought companionship in each other, but truly those two characters are so different, wonder if they can make a functional couple. I'd see them more as friends with the occasional benefit than anything else.
Besides, the way Diana just decided to distance herself from Steve Trevor, by telling him she would ask for another to serve as liaison with the Justice League in his place confirms that she still care a lot a bout him since she's willing to let another person take the risks that come with the position in his place. This seems to indicate that she care more for his well being than for that of another person. On the other hand, as Steve points out himself, he is often in danger regardless of his association with the League, so it's not like not working with them will protect him. Knowing this, it feels more like Wondy doesn't want to feel guilty should he be killed by one of the justice League's enemies.