My Warden came from a noble and privileged background. Born and raised as "the spare" in the Cousland family, he was never expected to take over Highever as teryn (though some said he would have been good at the job), and in some regards, he felt without an identity compared to his elder brother because of this. As such, he'd turned into a bit of a playboy (hence having a one night stand with Iona). I got the feeling from the origin story that his mother had been trying to marry him off for some time, but had been unsuccessful.
I picked the same Origin,the same gender but my Warden lifestyle was less headcanon end and more akin to the game revelations.
A Warden which is from the Cousland family isn't in my mind second or a spare to anyone much less to Fergus,since pretty much some soldiers,Eleanor and maybe even Bryce believe that the younger is indeed better than the eldest
(which is a shame for the nobility mindset) not that Fergus is all that bad....
The Noble Cousland is a strong Warrior/rogue who use to win several tournaments and competitions in Ferelden,so your identity among the nobles and commoners is pretty much stronger than the one of Fergus(who however is the eldest and more important for tradition) Loghain in person already know you or your reputation since he said at Ostagar that you look familiar for him,a face that he already saw.
There are of course some old nobles (The tavern at Denerim) who only know your parents ,but they are the old generations.
Also from what i understand from the introduction the character possess also great deal of knowledge thanks to the wealthy family and the libraries,since i still remember that in conversation with Aldous (high cunning required) the character show to know very well events of history and be capable to grasp things that s/he doesn't yet know.
Also (and this surprised me) In conversations with Dairren the character can demonstrate devouring interest towards the old gods,Dragons and their link to the darkspawn long before to become a Grey Warden,which make me to question on how much is the real knowledge of the character at the beginning of the game (Nobles have the possibility to study a lot).
So no i didn't roleplayed a spare/playboy Cousland because it would have been to OOC for me,an Amell or a city elf or a Dalish or an Aeducan maybe it would have work for me,for the Cousland not so much.
Yes there is Iona/Dairren but this doesn't prove anything,they are captured by the allure of The noble Waren, the contrary is not mandatory