Well, there is a bit of expansion on that front this time around too. If she has a date with Marc you can see a bit of it which I think sets up the relationship quite a bit better. I think the biggest issue with the Marc stuff in the initial release is you only hear about him second hand. Here you get the option on whether or not she goes on the first date with him as well as
I always liked the concept of Marc in that it is very clear early on that Nikki used sex to find love. Look at the situation with Grant from the early releases she thought that sex would lead to a relationship, but the guy just used her. Marc from the little we know of him is the first person outside of Taylor who tries to see her for who she is. It is a fitting end for the journey. I've seen it happen IRL, someone who is banging up a storm in college finally settles down with someone a lot more reserved or even a virgin. Party girls aren't always party girls forever. I think the new scene toes the line of introducing the character enough without bringing in a totally new person to get to know very late in the game. And he only shows up in very specific playthroughs now. And of course it helps that since Nikki is an option now players don't feel blindsided by her ending up with someone else based on a single choice made ages ago.