By traditionalist, do you imply some level of fundamentalism?
Because if so, I certainly cannot see a (for lack of better phrasing) fundamentalist Dalish willingly entering a romantic or physical relationship with a human. In fact I believe it would be difficult for someone who is a devout follower of any faith in Thedas to be interested in someone of a different one. I doubt they would even be comfortable working with as many humans and Andrastians as they would be. Difficult, but I hesitate to say impossible. People change (or are hypocritical), after all.
If you simply meant a Dalish Inquisitor who follows the cultural and religious traditions they grew up with, then I believe they would have to be accepting of the sacrifice that comes along with romancing someone outside of accepted conduct, and willing to potentially ostracize themselves. Particularly so for male Dalish, as there would be no chance of ever returning to his clan once taking on Cassandra/Josephine/Iron Bull/Dorian as a significant other, lovely as they might be. We know that non-elven individuals are not welcome among the clans.
Female Dalish would possibly have the option of doing so were it given, provided they romanced an elf like Solas...although even he may have reservations about joining a Dalish clan, seeing how he could have done so at any time if he'd wanted to. And I don't think we know enough about the elven views on homosexuality - although we can glean some implication that it would go against the rite of passage for city elves as they're forced to marry; and against Dalish as it would not be conducive to building numbers - to say that Sera would be welcome to return with a female Dalish to her clan. Not that she would anyway, since she apparently hates the outdoors.
Either way you look at it I doubt we'd be heading back to our clans other than in our head(canon)s. Responsibility and the maintenance of all that Inquisitorial power will keep our Dalish PCs tied where they are.
Aaand I rambled. Meh, whatever.