I think this is the most important thing write any couple. If they don't compliment each other, what's the point in them?
One of my favourite odd but very entertaining couples that could have fallen into abusive but actually didn't was a niche manga that told the villain's side of the anime. And these two fucked up former child soldiers were sadistic cold commanding planner and sniper who cries at movies about animals and the energetic, book dumb, womanizing combat specialist with good instincts. And their relationship, while could have fallen into controlling from the more obviously dominant sniper character, but balances it with a lot of "because my gut says so" being right and an equal amount of "yeah I know you're trying to be protective but I'm gonna do my thing anyway" and in the end the seemingly softer character being the one very much in control and just letting the other do their thing because they trusted each other when it came down to it and it was fantastic and a mess and incredibly fun to read and I wish I could remember it's name.