I've never actually done Leliana's romance with a male Warden myself. Just watched it on YouTube to see if there are any differences.
In fact, I've barely even played a male Warden. I can't drift from my canon female Dalish for too long, every other Warden feels like an imposter to me. :S
The male Warden version was missing two of my favourite scenes in the female Warden version, from what I observed. (Hair conversation, and the "And I...love you. It's so wonderful to say that to someone again.") I guess it's compensated for with more party banter, but eh, as I said. I only play one thing, never done it. *shrugs*
The first Warden I played was male I think. A Cousland (I always play human first). Then I played female Cousland. Then male CE. Then female CE. Then... you get the idea. I played every origin at least twice, male and female.
I think I played the male CE about three times, and the female CE... I can't remember, but I had a lot of versions of her (all played to the end). Rogue, warrior, sweet, snarky, brunette, blonde, red head, different hair styles... So many runs.
My 'canon' Warden is a blonde, green-eyed City Elf with the ponytail and bangs style (the one Leliana sports in her DLC, incidentally). She's best friends/sisters with Morrigan and lovers with Leliana, so I have a complete set! Blonde, brunette, red head! (stop judging me this instant!)
If Leliana becomes Divine then... She's the lover of a Blight tainted Elf and the honorary aunt of a child who was born from an apostate and the king of Ferelden through a forbidden magic ritual to house the soul of an Old God...
Leliana is a weirdness magnet.