Since we are apparently sharing whom our Wardens tend to romance, here's mine.
Amell: Leliana (They both seemed to be looking for someone to accept them as they really are. I also want to see if Leliana and Cullen have any words on the subject since Leliana gets involved with his crush.)
Brosca: Alistair (Both she and Rica have stolen the hearts of future kings.)
Cousland: Morrigan and Leliana and Anora (It's good to be the King.
)
Mahariel: Zevran (Both were elves without a home so were kindred spirits.)
Tabris(canon Warden): Nobody. She doesn't believe in sex before marriage.
Indeed, you stud you! 
Amell: Alistair. He doesn't need to marry me, I know who has the court ear.
Brosca: Zevran. Both were products of a rather crappy environment, both rogues, and both were travelers without a real home to call their own.
Cousland (my "cannon" Warden): Alistair again. That's Queen Cousland to you, although she did have a fascinating night at the Pearl. 
Mahariel: Leliana, both being archers and great lovers of beauty. Her awe of the Dalish and her willingness to treat my Warden as an equal went a long way. This was also the only Warden that did the US. Leliana's epilogue slide was very depressing. 
Tabris: Leliana and I played my Tabris a bard as well. She loved the idea of being involved in The Game and being a spy. She's also the only Warden I've played with a set sexuality in mind (she was a lesbian, had known it for years and she questioned the arranged marriage every chance she got.)
Aeducan: Nobody. She didn't find anyone attractive, since she really only liked dwarves.