This is in no way an attack on Diana shippers. You guys are great, and I respect you just as much as my Tiana shippers. If anything in this is offensive, please let me know and I'll change it. 

Now, I'm not completely against Diana. If it happened, I'd be disappointed, but not mad. Here are just a few reasons why I don't think it would work out, and feel free to counter these in the comments. 

1. Dex's Character Development

This is my biggest reason for not shipping Diana as much. Dex was pretty much the first character to openly dislike the Vackers, and it made him really interesting. It gave us another side to the Vacker's richness and popularity and how it affected everyone. Then, thankfully, Dex made friends with Fitz and everything was good. But Dex is only friends with them. He's not besties with them, but he's good friends with Biana I suppose. I just feel like if Dex fell for Biana, it's just be one more person who loves the Vackers just like everyone else does. I feel like one of his major qualities would disappear. And I know, he was mainly aggressive towards Fitz, but he also didn't particularly like Biana either. I totally love that they're friends, but I feel like a major part of Dex's personality is his hesitation/wariness of rich people. 

2. Rebound 

Now, this reason would be nullified if Dex and Biana got together in an epilogue of some sort, but if they got together now, or even in book nine, I just feel like it would be pretty soon after Sophie rejected him. Now, I know teeeeechnically all she did was make him realize he "didn't like her that way", but still, it might as well have been a rejection. I feel like he might still be a bit sensitive in a relationship this soon after that. Even though he seemed pretty okay talking about it in Flashback. I don't even know what I'm talking about anymore. 

But yeah, that's it. Again, no offense Diana shippers, I still think it's a cute ship