Well my recommendation was not a condemnation of the Cullen romance, which I haven't even played...
You would be hard-pressed to find a bigger Hawke x Fenris fan than me, but the truth is that you can easily play the entire game without ever even recruiting Fenris let alone romancing him and nothing changes. His inclusion adds "flavor" to the story but it isn't exactly woven throughout.
But Solas is a different kind of romance. It would be like romancing Loghain or Mereidth... not that I would want to lol and NOT that I'm saying Solas is a villain. But Solas IS the story of Dragon Age, so when you romance him it's like romancing the actual story. Hard to put it into words.
Never considering it a criticism, trust me

. I was just making an observation about Cullen's romance, and the fact is, considering his and Solas' romances could be considered "tacked on" due to being added last, it's kind of funny they're generating the most buzz.
I understand what you're talking about. He's a central thread of the DA story and it's a layer deeper than any of the others to date.
I suppose you could kind of say that about Anders as well, or could if they'd been given more time. Gah, I need to win the lottery and then go to Bioware and dump money on them to remaster DA2.
I've been playing through Hawke X Fenris, and it's actually sweet. I haven't hit the finish yet but I'm liking him more and more.
Romancing Solas has its pros and cons, depending on what's important to you. Agree with CA that Solas's romance is more central to the story, but it's also pretty slim in content compared with Cullen. No woo breaks, for example. Fewer cut scenes. If your approval is too high, you will get fewer of his stories when you visit him. You don't lock in the romance until almost the end. I ended up skipping a lot of side content just to get the romance moving along, because it was a bit of a desert at times. But is it worth it?? OMFG YESSSSS!! It's worth it just to SEE and play through Trespasser, and if you're writing Solas, Solavellan hell is an important vantage point. For science. And hope. And epic tragedy. And glorious glorious suffering. 
(edit: Plus, it's pretty easy to imagine Cullen is still in love with you, even if you go with Solas, which means... OPTIONS. ahem)
It sounds like I might need ativan during the process; I will have to take that into account. It also almost sounds like it might make more sense to recruit the templars on the playthrough. I'd do fair weather friends, but I'm not sure my heart could take it.
I admit there's one story of his that had me jumping up and down my first playthrough... the hut in the Korcari Wilds. I was bouncing on my toes even before the end credits scene. And with the end credits scene, my brain just blew up at that point.
Writing Solas has been interesting, especially since I'm doing the Hawke as Inquisitor shtick, which unfortunately isn't something I can pick up much reference on, unlike say Hawke and Cullen.
Glorious glorious suffering? I swore when Marcus got dumped into that refrigerator tube I wouldn't do that to myself again, and then when Angel's "moment of true happiness" came between him and Buffy. Aww, what the hell?
On a more serious note, the lock happens after he takes you out and tells you about the tattoos?