TFNT jules
I think the Bellarke dynamic was planned from the beginning but they didn't know whether it was going to be romantic in the future. I think they noticed the chemistry and decided it was an interesting dynamic but they were testing the relationship with the audience first.
Eliza and Thomas thought people were going to root for Clarke/Finn because they were THE couple this season so they were a little surprised by all the attention Bellarke got.
I think S2 is going to be great because the writers now have the reactions from the critics and the fans.