One of the biggest issues with your kits is the lack of characters to populate them. Sure, you can argue that you concentrate on environment design, but in order to be really useful, you should consider providing a couple of rigged characters in the theme of the kit to really allow for “out of the box” scene creation.
You could approach this in a similar way to Big Medium Small’s kits of providing static posed characters AND characters rigged for Mixamo so they would work with any DCC. See: https://www.bigmediumsmall.com/collections
Customisable materials would also be required for mass population.