Some of my favorite couples are:
Phedre and Jocelyn in Kushiel's Dart
Jamie and Claire in Outlander
Beatrice and Benedick in Much Ado About Nothing- I know this is Shakespeare so it's not everyone's cup of tea, but this is a very light-hearted, fun play and the characters all have a wicked sense of humor.
Jillian and Ben in Heart of Fire
These aren't for everyone, but the ultimate light-hearted, guilty-pleasure, paranormal romance books imo are:
Jared and Samantha in Here Be Sexist Vampires