he could have played it in so many different ways

To the people that say SasuKarin and SS are the same - Something simple

Even if you don’t believe Sasuke loves Karin, I can accept that but let’s look at it from a different view. We all know what an opportunist Sasuke can be. He has been talking about reviving the Uchiha clan for ages. Some interpret it differently but the way I understand it is, that he wanted to make the clan stronger than it has ever been, so no one could push it around anymore.

One doesn’t need to be in love to get married. There are other factors that play a role and a genius like Sasuke would sure as hell take them into account. 

Karin is an Uzumaki. They possess an extremely powerful life force, which means they could have as many children as they want without harming their bodies. 

Uzumaki’s are of Senju bloodline, if you mix an Uchiha and a Senju the possibility of a Rinnegan developing is damn high. 

All in all, an Uchimaki child would be the strongest beast ever and if Sasuke had been the same Sasuke he was before Kishi ruined him and threw all of his ambitions to the dogs, it would have made sense for him to pick Karin. Love or not. 

But of course, Kishi would have then given Sasuke the more powerful child and that just can’t happen since Bolt is the hero of the new mini series.