Behind every great passionate alpha couple (that the story focuses on) theres a comedic beta couple (for the subplots) and I always love the Beta couple the most. They flirt in unconventional ways, go on wacky adventures, and while they might not get the first big damn kiss of the story, but they always capture my heart.
Also they tend to be older couples, odd couples, rivals or weirdos, basically they get a lot of the more interesting dynamics.