I don't know why I keep doing that. Taking a perfectly good render and introducing all the issues that plagued us in the past and have luckily moved away from them. But I like it.
Anyways, I just did a reset on Daz and had to download all the assets/plugins, etc again. Or well, the ones I remembered. At least now it stopped throwing errors at me every few clicks and/or crashing. The model is most likely not exactly the same as before but close enough for me to be happy about it.
And since not everyone is into big walls of text, I'll put the technical details in a spoiler for those that are.
So, here's the render as it came out of Iray with no adjustments.
And here's the post version of the image.
If anyone has any suggestions, please share.
I'm quite happy with the result, but there's always room for improvement.
Oh! And for the fun of it, or for the sake of completeness, here is the real size of the photo you'd take. 46mm x 62mm for the photo, 56mm x 83mm with the frame.