Like in the first ship rants chapter, these are just my personal observations and opinions.
Denzo (Damon Salvatore + Enzo St. John):
Lowkey I love it, they definitely had sexual tension when Enzo was first introduced. They'd have the best friends to enemies to lovers story. Either way I would have loved to see that.
Klefan (Klaus Mikaelson +Stefan Salvatore):
YES. Forget Stelena, this one is amazing. Klaus definitely had a bit of a weak spot for Stefan. They definitely go well together. Throughout the entirety of Klaus' career he has a reputation of being paranoid and solitary, and Stefan would be the one that changes that. None of his siblings or friends or previous lovers quite changed that, but Stefan seemed to affect Klaus differently.
Also, side note, I really wish they'd experimented a bit more with queer characters besides the side characters that only stay half a season, like the "token gay" character. (Another side tangent, Elena's mom was bisexual. It was a discreet reference, but at some point she had compelled a guy and girl to dance as a show for her, and the girl had a bite mark on her thigh. I don't remember who had asked her if the guy was gay because she'd found them both at a gay bar, but I remember she responded something along the lines of "he's not gay right now". There are a lot of things wrong with what she was doing
Steferine (Stefan Salvatore + Katherine Pierce):
This relationship was toxic no doubt, and I have mixed feelings about it. The question, for me, is whether or not Katherine cared for Stefan. I do think that she was fond of him, hence why she came back for him, but she didn't prioritize him. Not in the beginning at least. He was like a side mission for her. Her attraction to him when she came back was not romantic, I don't think. It was an obsessive crush in which her determination to win him over came from her sense of entitlement. Stefan probably did love her at some point but those feelings obviously stopped. He forgave her, but the romantic feelings stopped when he learned of her betrayal.
Elijah + Katherine:
This was quite an interesting ship to experience. At first I didn't get why Elijah loved Katherine, I thought that her puppy eyes would stop working when he realized what kind of person Katherine really is, but then he went and fell in love with her again. I didn't hate this coupling, but not one of my favorites.
Mabekah (Mat Donovan + Rebekah Mikaelson):
Matt Donovan got way more than he deserved. The powerless side character pulled Caroline and Rebekah and Katherine. I didn't hate this one, but it felt like they tried to mimic the 'I can change him' (Matt tried to change Rebekah) with them but it didn't quite execute right. It was alright.
Elejah (Elena Gilbert + Elijah Mikaelson):
I don't entirely hate this ship. It's not any kind of epic love like Klaroline or Delena, but if it had happened their love would have been soft and sweet. As showed with Stelena, soft and sweet would not have been enough for Elena, so it probably wouldn't last. But I would have liked to see it happen.