If you didn't have to worry about softening/hardening, what would you support?

First choice: My natural reaction was to stand back and let Leliana get on with her job. I was relatively new to the team and since I was playing an elf (first a mage and then a rogue), they wish to observe how humans manage these things. They were there to spy on the humans when all is said and done. It didn't seem my place to interfere as I was not leader at this point.

Second choice: I don't think leaving the agents in the field would have made much difference as the numbers in opposition were too great. Better to call them back and re-group on the defences.

Third choice: By this point my elf Inquisitors had spared enough people by giving them something to do on our behalf that killing Natalie seemed too extreme. Either taking her prisoner or letting her go seemed more appropriate. Since I had been facing down the Chantry since the early days and Josephine had been working hard on the diplomacy front, showing mercy also seemed a more prudent move than butchery. If Natalie doesn't appreciate it, well she isn't that important anyway and if she acknowledges the merits of my action then she can report to the doubters that if nothing else the Inquisitor is not a bloodthirsty tyrant, particularly important for improving the image of the Dalish.

I would point out that these were exactly the decisions I took first run with my elf mage Inquisitor and of course ended up with a hardened Leliana as a result. With meta knowledge I could alter my first decision with my next run but it would have been bad role playing because if anything my male elf rogue would be even more likely to simply observe rather than interfere. He would certainly not advocate mercy, why should he since they would not do so in the clan? However, throwing his weight around and encouraging her to kill the spy might only reinforce the anti-Dalish stories that Josephine had told us about, so taking a passive stance was both informative and expedient.

However, having observed the ruthless monster that Leliana becomes, my Inquisitors definitely do not advocate her becoming Divine. My first Inquisitor deliberately voted for Cassandra as an alternative.   My rogue didn't actively support anyone but got Leliana, chiefly I think because of his decision to put Briala on the throne of Orlais.