I know there are already some favourite contestants and couples but i want to talk about the unpopular opinion here. The opinions that are not very popular but deserve to be heard and said. 

My first unpopular opinion is that Sian should end with jeongsu.  And Theo should be with someone who reciprocate the same energy.

My 2nd unpopular opinion is that Yuk is a player. I didn’t like the way he ignored youjin. he could’ve tried to talk to her but instead waited for her to talk to him and pinned the blame to her. They could’ve made a good couple. Its sad they didn’t last.

I think if anything, Sian should end up with Yuk. Jeongsu is a red flag, anyone can see that. Including Sian, I'm pretty sure. And like you said, Sian isn't reciprocating Theo's energy (which sucks because I shipped them at the start).

I don't exactly love Yuk, but Sian is the only girl he genuinely made an effort to approach. Like, he was actively playing with her in the pool, and then he made his feelings for her clear. He hasn't done that with anyone else.  He was really vague with Minseol, but he made his feelings clear with Sian.