I can't comment on things like snow since I don't have any of your products that use it, but the rest converts ok enough. The only thing that might be needed for Iray is good quality displacement and normal maps, otherwise it's pretty noticeable, Iray really tends to make things stand out, especially for stuff in the foreground. Looking at the texture folder, for city block 4 and block 5, those would just need normal maps, maybe displacement for some of the textures, and luminosity maps for neon and lights. They are small enough that there wouldn't be a big resource impact when loading a few blocks either. Stonemason had to start adding normal, lumenosity and translucency maps when he moved over to Daz/Iray, otherwise his maps are similar to yours in terms of quality. Your diffuse maps look a bit more resource friendly actually. I can see them selling well, you always had prime content here.