I like Nate better than Dan (I like Dan too don't get me wrong) but Nate being Gossip Girl would've made way more sense than Dan given their characters. 

Sort of similar to how I think Fitz being Hydra would've been a more shocking and interesting twist than Ward on Agents of SHIELD, except that I do actually actively dislike Fitz. That's not why I think him being Hydra would've been a better twist though.