In all due respect, this game was meant to be played from each gamer's personal canons. All DA titles interwoven so that the setting follows what each person feels as their preferred outcomes.
Basically, asking which race is better from the narrative perspective is completely pointless.
With that said, however, if you are looking for which Inquisitor Bio Ware will choose for their vanilla canon, then the most likely option will be the human one.
Originally, DAI was going to repeat DA2 with a human only protagonist but they later changed that because the public demanded multi-racial protagonists and they had to set their record straight after the ME3 ending.
This is why DAI doesn't have origin stories, they already made the first half of the game with a human only Inquisitor in mind and that's why all other races have little development until you move to Skyhold.
That's also why only the human Inquisitor has a major role in the Conclave whereas the others are either spies or mercenaries, they were retconned to be there and hence their presence feels more out of place.
To be more specific, Travelyan is a noble whose family has strong ties to the Chantry and the Templars and he/she was there either on their behalf or, if he/she is a mage, on behalf of the Mage Rebellion. Regardless if you play as a warrior/rogue or a mage, that backstory fits like a glove to explain how he/she got to the point of interfering with Justinia's sacrifice.
By contrast, Adaar was hired for Chantry security despite Andrastians having huge mistrust and bigotry towards Qunari while Cadash and Lavellan somehow infiltrated a place almost exclusively filled with humans while wearing a huge tattoo on their faces screaming "I AM A SPY!".
I get that Lavellan has access to a lot more lore later in the game given how the story shifts from mage-templar conflict to ancient Elven lore and that her romance with Solas opens up a lot of dialogues from the man behind the scenes which would be otherwise unavaiable but she falls out of place when placed in the role of Inquisitor.
Another reason for choosing Travelyan over Lavellan in how the game excessively punishes the later and favors the former.
Regardless if you play as pro-mage, pro-templar, faithful or atheist, Travelyan will wind up succeding in what he/she tries to accomplish while coming out better from each situation he/she encounters. Not just that, he/she embodies the modern world of humans, for good or bad, clashing against ancient mages who seek to restore forgotten glory at the expense of everyone who lives in the present.
Regardless if you play as pro-mage, pro-templar, faithful or atheist, female Lavellan keeps getting kicked in the guts by everything around her, potentially ending up as the last surviving member of her clan and abandoned by the only man she ever loved. Not just that, she embodies the lost world of elves which the game mercilessly deconstructs into being the bringer of it's own demise.
When push comes to shove and we face the true antagonist, Travelyan can potentially challenge Solas beliefs on the basis that humans and other species are better than he takes them for but Lavellan, unless played as extremely cosmopolitan, can only challenge him on behalf of Elves or love which doesn't struck the same message as modern world vs old world.
Last of all, BW seems to display mostly the human Inquisitor in their media and especially the rogue one at that.
My guess is that their canon follows a pattern as to give each class proeminence. Vanilla DAO was female Dalish warrior and vanilla DA2 was male Hawke mage so they will most likely pick male or female human rogue for Vanilla DAI when DA4 comes out.