A non romanced Warden Alistair. Good grief even if it meant him leaving like he does or if you kept the Wardens in Orlais and he became the Warden "Agent" at Skyhold. Cullen would of never had a chance if I could of romance Alistair, even if it didn't last throughout the game. Second one would be Fairbanks, if he stays as a Agent for the Inquisition, he was super cute and had a sexy voice actor too,lol.
I support Scout Harding. She's really cheerful, dedicated and interesting character present on many occasions - wherever Inquisitor goes, Harding is before them. They could've just elaborate the mini-romance (no jokes) that's already been written. Also no-dwarven-LIs. It's a shame, because it feels like the dwarves in general are under-represented in comparison to elves and (even) qunari. I didn't played Descent, I admit I could've missed something. I don't think Varric would be a good candidate for LI, though. Aside from the fact that he's taken (and it's good to have a character that is not interested in a protagonist because of logical reasons), he seems to be in his best shape in DA2. I like him in Inquisition of course, but I feel his presence is a little bit forced. Some characters find their place in the Inquisition, new friends - almost a new family. Varric's left his heart in Kirkwall. He'll always be a friend to Hawke first.
I think there should be a dwarf romance option -- Harding and/or perhaps Varric won't be forever holding a candle for a woman married to another... He deserves a woman all his own.
Other than that, I can't complain -- except, take me with you, Solas!
Abelas would be great but I think beyond the scope of the game and would probably also be an elf-only option but maybe not... It would take him time to come to terms with the way the world was... Perhaps he could have assisted the Inquisition in some capacity and at the end there is just the hint of hope for things to come...
Varric, again. Forever salty that we couldn't romance him two games in a row. Like, I know he's in love with Bianca, but she's really not worth his time. She just sits there stringing the poor guy along, in my opinion...
Also, why can't I romance Cremiscius Aclassi? He would be a wonderful romance option.
Personally for my character, either Morrigan or Leliana if they weren't involved with the Warden. Or Calpernia, I've always found her intriguing. Also, members of the Chargers, I wish they'd done more with them individually. And Harding with the signature bioware half-romance.